integrated physiology/obesity -...

A496

For author disclosure information, see page A751.

CATEGORY

& Moderated Poster Discussion

Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS

ADA-Supported Research

INTEGRATED PHYSIOLOGY—CENTRAL NERVOUS SYSTEM REGULATION OF METABOLISM

mean follow-up of 6 years, K-MMSE score was significantly decreased with 1.0 (interquartile range of 4.0), homeostasis model assessment of insulin resistance (HOMA-IR) was not significantly changed during follow-up.

Results: Participants with more decreased K-MMSE score (D K-MMSE) had shorter duration of education (p = 0.006), older age (p = 0.015), higher baseline K-MMSE score (p < 0.001), and increased insulin resistance (D HOMA-IR, p = 0.021). The correlation between D K-MMSE and D HOMA-IR remained significant after adjustments for age, gender, baseline K-MMSE score, duration of education, baseline Korean geriatric depression scale, smoking status, history of diabetes and hypertension, body mass index, and apolipoprotein E4 genotype status (B = -0.168, p = 0.028).

Conclusions: During 6 years of follow-up in elderly Korean population, increased HOMA-IR was significantly associated with decreased cognitive function.

1872‑PO‑Linked β‑N‑Acetylglucosamine Signaling in Pro‑Opiomelano‑cortin Neurons Mediates Brain‑to‑Fat Communication to Coordi‑nate Whole‑Body MetabolismSIMENG WANG, HAI BIN RUAN, MIN DIAN LI, KAISI ZHANG, BICHEN ZHANG, YUNFAN YANG, XIAOYONG YANG, New Haven, CT

Proopiomelanocortin (POMC) neurons in the arcuate nucleus of hypo-thalamus suppress feeding and promote energy expenditure. The function of POMC neurons is regulated by a variety of metabolic hormones. Known as a metabolic sensor, O-linked β-D-N-acetylglucosamine modification (O-GlcNAcylation) of intracellular proteins is catalyzed by O-GlcNAc trans-ferase (OGT). Here we report that OGT is required for POMC neuron action on adipose tissue and whole-body metabolism. POMC neuron-specific OGT deletion reduces neuronal excitability, increases food intake, lean mass and fat mass. These correlate with impaired lipid catabolism in white fat depots and reduced thermogenesis. The respiratory quotient is increased in OGT knockout mice, suggesting an increased preference toward carbo-hydrate utilization. Under the high fat diet condition, POMC neuron-specific OGT knockout mice exhibit pronounced body weight gain and adiposity, but improved glucose tolerance and insulin sensitivity. Collectively, these results reveal that O-GlcNAc signaling in POMC neurons is a key node of brain-to-fat communication to coordinate whole-body metabolism.

Supported By: National Institutes of Health (R01DK089098, R01DK102648)

1873‑P

amplitude and maximum rate of rise were found to be reduced in CIRKO compared with WT (F/F0 0.79±0.05 vs. 2.2±0.2, n= 20/group, p<0.05 and F/F0 per sec 28±2 vs. 77±7, n=20/group, p<0.05 respectively). We also found a reduction in Cav1.2 expression (main trigger for Ca2+ transient) and current in CIRKO mice with no difference in the steady-state activation properties of the channel (gene expression 44±5%, n=10/group, p<0.05; protein expres-sion 62±1%, n=3/group, p<0.05; 35% decreased in the macroscopic current at +10 mV (-21±1 A/F, n=6 in WT vs. -14±2 A/F, n=8 in CIRKO, p<0.05).

In conclusion, our finding suggest that impaired cardiac insulin signaling per se is involved in the Ca2+ mishandling observed in the systemic models of diabetes.

Supported By: National Institutes of Health (5T32HL007576-30); Nora Eccles Treadwell Foundation

1870‑PSustained Activation of Beta‑Adrenergic Receptors Enhances de Novo Lipogenesis in Adipose TissueADILSON GUILHERME, DIANXIN LIU, BATUHAN YENILMEZ, DAVID J. PEDERSEN, ELIZABETH HENCHEY, FELIPE HENRIQUES, SHEILA COLLINS, MICHAEL P. CZECH, Worcester, MA, Orlando, FL

The de novo lipogenesis (DNL) pathway in adipocytes appears to influ-ence whole body metabolic homeostasis, perhaps by producing bioactive lipids that modulate systemic insulin sensitivity. Thus, the identification of regulators of DNL in adipose tissue (AT) is of high interest, in particular the mechanisms by which obesity downregulates DNL. Here we investigated whether the sympathetic nerve system (SNS), via activation of β-adrenergic receptors, modulates the DNL in AT. Stimulation of SNS outflow to AT depots in cold-exposed mice (6°C) enhanced the expression of several genes in the DNL pathway, including ChREBPβ, ACLY, FASN and ELOVL3 in AT. Similarly, treatment of mice housed at 22°C with the β3-adrenergic receptor (β3AR) agonist CL316243 increased the expression of DNL genes in AT. Conversely, when mice were housed at thermoneutral conditions, in which SNS outflow and the βAR signaling pathway in AT is negligible, a strong downregulation of the DNL genes in AT depots were observed. In the absence of endog-enous SNS drive, DNL in AT could be partially overcome by treatment with CL316243. Based on our recent findings that mTORC1 is required for β3AR-induced thermogenesis in AT, we investigated whether mTORC1 was also necessary for β3AR-regulation of DNL genes in fat. While the mTORC1 inhibi-tor rapamycin completely blocked induction of the key thermogenic mediator UCP1 by CL316243 or by cold-exposure treatment, it failed to inhibit DNL gene expression in AT under these same conditions. In contrast, adipocyte deletion of the mTORC1 subunit Raptor prevented both thermogenic and DNL gene expressions in concert with a strong inhibition of β3AR expression. These data suggest multiple outputs from the mTORC1 complex in response to βAR signaling. Overall, these results indicate that SNS outflow and sus-tained βAR activation stimulate the DNL in AT. Our findings suggest that dys-regulation of βAR signaling might contribute to suppression of DNL genes and AT dysfunctions associated with obesity.

Supported By: National Institutes of Health


1871‑PIncreased Insulin Resistance Is Associated with Decreased Cogni‑tive Function in Elderly Koreans: A Prospective Community‑Based Cohort StudySUNG HYE KONG, BO KYUNG KOO, MIN KYONG MOON, Seoul, Republic of Korea

Objective: It is well-known that diabetes is associated with increased risk of cognitive dysfunction. However, it is controversial that whether periph-eral insulin resistance effects on cognitive function in longitudinal studies. We aimed to evaluate whether change of insulin resistance was associated with cognitive decline in elderly Korean.

Method: The study was conducted in the Ansung Cohort Study, the ongo-ing prospective community-based cohort study in Korea. A total of 5,018 participants aged over 40 years at baseline were followed up for a mean of 9 years. Of them, the final analysis was performed in 450 participants aged over 65 years who were evaluated with Korean mini-mental status examination (K-MMSE) at both baseline and follow-up. Pearson’s correlation analyses and multivariate linear regression analyses for change of K-MMSE score were carried out.

Results: Mean age at baseline was 69.2 ± 2.9 years, and 234 participants (48.0%) were men. Mean duration of education was 7.3 ± 3.4 years. During a

WITHDRAWN

A497


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



1876‑P

1877‑PExenatide Modulates Visual Cortex Response to Food ImagesGIUSEPPE DANIELE, PAOLA BINDA, ROY ELDOR, RALPH A. DEFRONZO, JACK LANCASTER, PETER FOX, STEFANO DEL PRATO, MUHAMMAD ABDUL-GHANI, Pisa, Italy, Tel Aviv, Israel, San Antonio, TX

Introduction: GLP-1 enhances metabolic activity in neural tissue and mod-ulates food-related behavioral responses.

Objectives: We investigated whether this effect may involve changes in early sensory processing of stimuli such as visual appreciation of food images.

Methods: The effect of Exenatide (Ex) on fMRI responses to food and non-food pictures was evaluated in 10 normal weight (NW: age 40.2±6.9 yrs; BMI 24.8±0.9 Kg/m2) and 10 NGT obese subjects (OB: 49.4±6.1 yrs, 34.2±1.1 Kg/m2). fMRI responses to images were evaluated before and after i.v. EX (0.05 μg/min). BOLD signal at rest (BSR) was calculated as the average of the raw fMRI signal in the last 3 volumes of the rest blocks. Visual activations (BSV) were computed as % signal change relative to BSR.

Results: Under baseline condition OB had comparable plasma glucose (93±3 vs. 93±2 mg/dl) and higher insulin (11±1 vs. 6±1 μU/mL; p=0.002). BSR was higher in NW vs. OB in the parieto-occipital cortex (899±12 vs. 837±13 a.u.) with no effect on temporal and frontal cortex. Across occipital cortex, there was a negative correlation between BSR and BMI (r= -0.43; p<0.001). With EX infusion, there was no difference in plasma glucose (94±2 vs. 92±3 mg/dl) and insulin concentrations (32±9 vs. 30±6 μU/mL) in the two groups. BSV increased in a parallel manner in both groups over most of the cor-tex, extra-striate areas (lateral-occipital, sparing V1) and prefrontal cortex so that BSV was higher in absolute terms in NW but with similar percent increase (+15 vs. +17%). BSV was reduced in temporal pole in both groups.

Conclusion: BSR is higher in NW. EX modulated BSV responses to food images in a similar manner in OB and NW, though the former always had higher numerical BSV values. These preliminary results support a role for GLP-1 in food image brain processing.

1874‑PThe Ventromedial Hypothalamic (VMH) Glucagon‑Like Peptide‑1 (GLP‑1) Receptor (GLP‑1R) Promotes Satiety by Regulating the Activity of Key Nutrient SensorsMELISSA A. BURMEISTER, JACOB D. BROWN, JENNIFER E. AYALA, DORIS A. STOFFERS, DARLEEN A. SANDOVAL, RANDY J. SEELEY, JULIO E. AYALA, Orlando, FL, Philadelphia, PA, Ann Arbor, MI

The VMH is a glucose-responsive nucleus that regulates satiety. We have reported that delivery of the GLP-1R agonist (GLP-1RA) Exendin-4 (Ex4) to the VMH reduces food intake (FI) via inhibition of the nutrient sensor AMP-acti-vated kinase (AMPK). Since AMPK inhibition activates acetyl-CoA carboxyl-ase (ACC), the present studies examined whether Ex4-mediated suppression of FI via the VMH requires ACC activation. We also tested whether modula-tion of another hypothalamic nutrient sensor, mammalian target of rapamy-cin (mTOR), is involved. Whether the body weight-lowering effect of the GLP-1RA liraglutide requires the VMH GLP-1R was also assessed. Male C57Bl/6 mice were instrumented with VMH-targeted cannulae. FI was measured in response to VMH-targeted Ex4 following pre-treatments with the AMPK activator fructose, ACC inhibitor PF-05175157 or mTOR inhibitor rapamycin. Time-course changes to AMPK and mTOR signaling were assessed in VMH micropunches following VMH-targeted Ex4 and in GLP-1R-overexpressing CHO cells. VMH-specific GLP-1R knockout mice (GLP-1R KDDNr5aCre) were gen-erated using Nr5a-Cre and GLP-1Rflox/flox mice and compared to GLP-1Rflox/flox controls. Ex4-induced reductions in FI were not affected by ACC inhibition but were attenuated by pre-treatment with fructose and completely blocked by pre-treatment with rapamycin. Phosphorylation of mTOR and its down-stream targets p70S6K and S6 was elevated following treatment with Ex4 in CHO cells. In VMH brain punches, AMPK phosphorylation was reduced by Ex4 at 15-min post-injection, whereas phosphorylation of p70S6K was elevated at 120- and 240-min. The anorectic effect of peripherally-dosed liraglutide was preserved in chow-fed GLP-1R KDDNr5aCre mice. These findings demonstrate that the VMH GLP-1R promotes satiety by regulating the activ-ity of nutrient sensors, but it is not necessary for the effects of peripherally-dosed GLP-1RA on FI.

Supported By: American Diabetes Association (1-14-CD-01 to J.E.A.); National Institutes of Health (4R01DK097361, 1R01DK107652, 7R01DK082480)

1875‑PDisrupting Grb10 in POMC‑Lineage Cells in the Hypothalamus Improves Energy Homeostasis by Promoting Beiging and Energy ExpenditureFANG HU, HAILAN LIU, FENG LIU, Changsha, China

Impairments in hypothalamic insulin and leptin signaling pathways contribute to the development of obesity, but the underlying mechanisms remain elusive. We found that Growth factor receptor binding protein (Grb)10, a Src homology 2 (SH2)- and pleckstrin homology (PH)-domain con-taining adaptor protein that negatively regulates insulin/IGF and mTOR sig-naling, is highly expressed in the hypothalamus, particular in the leptin and insulin target neurons in the arcuate nucleus. Importantly, Grb10 expression in the hypothalamus was induced by high fat diet (HFD) feeding. Disrupting Grb10 expression in Pomc-lineage cells had no significant effect on locomo-tor activity in mice, but significantly reduced food intake and HFD-induced body weight gain, improved glucose tolerance and insulin sensitivity, and alleviated fatty liver in mice. Mice with Pomc Grb10 deletion also showed increased oxygen consumption rate and elevated thermogenic gene expres-sion in visceral and subcutaneous white adipose tissue (WAT), suggesting that Grb10 deletion in Pomc-lineage cells may promote energy expenditure by inducing beiging of WAT and thermogenesis.

In summary, our results demonstrate that deletion of Grb10 in Pomc-lin-eage cells protects mice from HFD-induced obesity by promoting beige fat development and energy expenditure, uncovering a key regulatory role of hypothalamic Grb10 in the regulation of whole body energy homeostasis.

Supported By: National Natural Science Foundation of China (31471131); Inter-national Science & Technology Cooperation Program of China (2014DFG32490); National Basic Research Program of China (2014CB910501)

WITHDRAWN

A498


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



1880‑PInsulin Receptor in Astrocytes Regulates Gliotransmitter Homeo‑stasis and Depressive‑Like BehaviorWEIKANG CAI, CHANG XUE, MASAJI SAKAGUCHI, MASAHIRO KONISHI, ALIZERA SHIRAZIAN, MENGYAO LI, ANDRE KLEINRIDDERS, EMMANUEL N. POTHOS, C. RONALD KAHN, Boston, MA

Insulin plays critical roles in the brain on both regulation of systemic energy homeostasis and neural functions, including cognition and mood. These effects have been largely attributed to insulin signaling in neurons, however, insulin receptors (IR) are also expressed in astrocytes. To explore the role of astrocyte IR, we developed both a conditional knockout mouse and AAV-mediated Cre-recombination models to delete IR in astrocytes. The astrocyte-specific IR knockout mice (AIRKO) exhibited numerous depressive-like behaviors, which could be rescued by treatment with the antidepres-sant imipramine. Dopamine signaling in the nucleus accumbens (NAc) is important for mood control, and dopamine release in the NAc was dramati-cally impaired in AIRKO mice. Likewise, knockout of IR from astrocytes in the NAc by direct injection of an AAV encoding hGfap promoter-driven Cre also induced depressive behavior, establishing the critical role of astrocytic IR in NAc on mood control. Mechanistically, IR-deficient primary astrocytes showed impaired insulin-dependent exocytosis and ATP release. This was due to the loss of IR-mediated tyrosine phosphorylation of Munc18c, which is required for vesicle-mediated transmitter release. In addition, IRKO astro-cytes displayed decreased expression of the glutamate aspartate trans-porter GLAST and decreased glutamate uptake. Consistent with the impor-tant roles of insulin on both purinergic (ATP-mediated) and glutamatergic signaling in astrocytes in regulation of dopamine secretion by neurons of the NAc, treatments with both the NMDA (glutamate) receptor antagonist ifen-prodil and purinergic receptor agonist 2-Me-SATP dramatically enhanced dopamine release in NAc. Thus, the insulin receptor in astrocytes regulates ATP release and glutamate uptake to modulate dopaminergic neuronal activ-ity in NAc and thereby has important effects on mood control.


1881‑PRhythmic Differences of Blood Glucose Circadian between Normo‑glycemic and Diabetic Nonhuman PrimatesBINGDI WANG, WEI QIAO, GUOFENG SUN, YONGQIANG LIU, JIQIU QIAO, WEI-WEI YE, XIAOLI WANG, GAO SUN, RYAN LINDQUIST, YIXIN (JIM) WANG, YONG FU XIAO, Taicang, China, St. Paul, MN

Disruptions of humans’ biological rhythms, such as shift work, can increase the risk of developing obesity and diabetes. As the nonhuman pri-mate (NHP) is a great model for metabolic research, this study compared the rhythms of blood glucose circadian among normoglycemic and diabetic cynomolgus macaques. Interestingly, the circadian rhythm of blood glucose in the normoglycemic NHPs differed from that in the diabetic NHPs (Figure 1, upper row panels). The glucose level in the normoglycemic NHPs decreased gradually from 3 am to a low level in 3 hrs and remained low until 3 pm (after-noon feeding time). However, the blood glucose level in the diabetic NHPs increased gradually around 7 am to a noticeably higher level and then was maintained until 9 pm. Postprandial hyperglycemia was observed following 3-pm feeding, but not after morning 10-am feeding. The circadian rhythms of physical activity and body temperature were similar among the normogly-cemic and diabetic monkeys (Figure 1, middle row and low row panels). Our data demonstrate that with the telemetry implantation method, the differ-ent rhythms of blood glucose circadian were observed among the normogly-cemic and diabetic NHPs, which may result from their different responses to both insulin and its counterregulatory hormones. Therefore, continuous glucose monitoring with telemetry device can be highly valuable for future diabetic research and drug discovery.

1878‑PStress‑Level Increments in Peripheral Glucocorticoids Affect Brain Regions that Regulate FeedingLISA PARIKH, SAMUEL ROSENBERG, ANIA M. JASTREBOFF, MUHAMMAD HAMZA, KATHERINE LAM, CHERYL LACADIE, DONGJU SEO, RENATA BELFORT-DEAGUIAR, JANICE J. HWANG, TODD CONSTABLE, RAJITA SINHA, ROBERT S. SHERWIN, New Haven, CT

Stress is known to affect appetite, craving, and food intake. Appetite, stress, reward-motivation, and decision-making are behaviors regulated by brain regions that contain a high density of glucocorticoid (GC) recep-tors. Peripheral levels of cortisol increase in response to stress, but how stress-level increments in peripheral GCs affect neural activity in these key brain regions in response to food images is not well-characterized. In order to address this question, we utilized functional MRI to measure the blood oxygen level dependent response to high calorie, low calorie (LC), and non-food images in 8 healthy lean individuals (6M/2F, age 24.2 +/- 4.5 yrs, BMI 22.3 +/- 2.0 kg/m2) following an overnight stress-dose hydrocortisone infu-sion (5.0 mg/m2 BSA/hr, total of ~120mg). The hydrocortisone condition (HC) was compared to a control overnight infusion of normal saline (NS). Condi-tion order was randomized and participants and investigator were blinded to condition. Salivary cortisol was measured at baseline and throughout the study. There was a six-fold increase in salivary cortisol while viewing food images on study day HC vs. NS (4.7 +/- 2.4 vs. 0.8 +/- 0.5 ug/dl, p<0.05). On study day HC vs. NS, we observed a decreased neural response to the food imaging task in the ventral striatum (hedonic, reward-motivation) and ven-tromedial prefrontal cortex (decision-making), and an increased response in the insula (interoception) (whole brain corrected, p<0.05). On contrast maps, this effect was largely driven by the response to LC images. Our preliminary results demonstrate that acute stress-level increases in peripheral GCs in healthy lean individuals decrease neural activity in hedonic, reward-moti-vation, and decision-making regions of the brain and stimulate the brain’s capacity to emotionally respond to food. These findings may have implica-tions for how stress-related hypercortisolemia and clinically administered GCs affect feeding behavior in lean individuals.

Supported By: Robert E. Lee and Clara Guthrie Patterson Trust, Bank of America, N.A.; National Institutes of Health

1879‑PDose‑Dependent Effects of Intranasal Insulin on Resting‑State Brain Activity in HumansSTEPHANIE KULLMANN, RALF VEIT, LOUISE FRITSCHE, KLAUS SCHEFFLER, HANS-ULRICH HÄRING, ANDREAS FRITSCHE, HUBERT PREISSL, MARTIN HENI, Tübingen, Germany

Insulin action in the human brain influences eating behavior, cognitive functions and also whole-body glucose metabolism. Most studies used intranasal insulin administration by a nasal spray and delivered insulin doses ranging between 20 and 160 U. However a systematic comparison of acute effects of different nasal insulin doses in healthy humans is still missing. We therefore tested the effects of placebo and three different doses of human insulin as nasal spray on regional brain activity and analyzed the absorption of insulin into the bloodstream. Nine healthy lean men received placebo, 40 U, 80 U and 160 U insulin spray in randomized order. Before and after spray, brain activity was assessed by resting-state functional magnetic resonance imaging. Plasma insulin, C-peptide and glucose were frequently measured. Nasal insulin administration dose-dependently modulated regional brain activity in the hypothalamus, the left amygdala, the striatum, and the lateral prefrontal cortex (pFWE-corrected≤0.05). In post-hoc analyses, only the insulin dose of 160 U reached the statistical threshold for difference from placebo spray for all these brain areas. We furthermore detected a dose-dependent absorption of nasal insulin into the bloodstream with the strongest increase in plasma insulin after 160 U nasal insulin (+ 30.9±29.8 pmol/l) that peaked around 15 min post spray and returned to baseline 15 min later. The fMRI responses were not correlated to this temporary rise in circulating insulin. Nasal insulin dose dependently modulates regional brain activity with stron-gest effects after 160 U. However, this dose is accompanied by a transient increase in circulating insulin concentrations due to a spillover into circula-tion. This is no major obstacle for the assessment of regional brain effects by imaging but should be mimicked in studies on peripheral metabolism. Our current results can be the basis for the design of future studies with nasal insulin to untangle brain insulin effects in health and disease.

Supported By: German Federal Ministry of Education and Research (01GI0925); Helmholtz Alliance; European Foundation for the Study of Diabetes (to M.H.)

A499


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



1884‑PDopamine D1D2 Receptor Agonist (DA) Therapy Improves Insulin Action and Glucose Intolerance in Streptozotocin (STZ)‑Induced Hyperglycemic MiceSHUQIN LUO, MICHAEL EZROKHI, TSUNG HUANG TSAI, SCOTT WATTERS, CHRISTINE CARDI, ANTHONY H. CINCOTTA, Tiverton, RI

Circadian-timed DA therapy has been demonstrated to improve glycemic control in hyperinsulinemic, insulin resistant states. However, whether such DA treatment improves glycemic control under hypoinsulinemic conditions has not been investigated and was the subject of this study. Male C57BL/6J mice (10 wks old) were fed regular chow and housed on a 14 hr daily photo-period and given a one-time STZ (120 mg/kg, i.p) (N=24) or vehicle (non-STZ) (N=6). Four days later fasting plasma glucose (FPG) levels were elevated in STZ vs. non-STZ treated mice (251±11 vs. 147±8 mg/dl, p<0.0001). Thereaf-ter, STZ mice were divided into two groups (N=12/group) and administered either DA (SKF 38393, 20 mg/kg [D1 receptor agonist] plus bromocriptine, 10 mg/kg [D2 receptor agonist]) (STZ-DA) or vehicle (STZ-V) while non-STZ mice were vehicle injected i.p. 13 hrs after the onset of light (onset of daily locomotor activity) for 9 days. Six days after the initiation of such interven-tion, STZ-DA treatment reduced FPG 43% level vs. STZ-V (185±13 vs. 359±31 mg/dl; p<0.0001) (non-STZ mice FPG: 146±4 mg/dl). At day 7 after treatment, glucose tolerance tests (GTT) were performed. Relative to STZ-V, STZ-DA mice had 39% reduced GTT glucose AUC (p<0.0001) without a change in insulin AUC, and increased insulin sensitivity by 2.9-fold (Matsuda Method) (p<0.05). At day 10 of the study, relative to non-STZ mice, STZ-V mice exhib-ited increased FPG by 2.6 fold (455±29 vs. 172±13 mg/dl; p<0.0001) and reduced plasma insulin by 48% (1.5±0.2 vs. 3.4±0.7 ng/ml; p<0.01). At this time point, relative to STZ-V treatment, STZ-DA treatment reduced hypergly-cemia by 52% (221±22 mg/dl vs. 455±29; p<0.0001) without altering plasma insulin levels (1.5±0.2 vs. 1.5±0.2 ng/ml) (HOMA-IR reduced 48%, 48±8 vs. 25±5 mmol/L*mIU/L, P<0.05). DA treatment improves fasting and GTT dys-glycemia in hyperglycemic, hypoinsulinemic STZ-treated mice by improving insulin action and without raising plasma insulin levels.

1885‑PThe Antidiabetes Effect of Intracerebroventricular (icv) Leptin (L) Administration in Mice Lacking Insulin Is Abrogated by Central Dopaminergic (D) Neuronal InhibitionSHUQIN LUO, MICHAEL EZROKHI, CHRISTINE CARDI, ANTHONY H. CINCOTTA, Tiverton, RI

An induced increase in central dopaminergic activity has been demon-strated to reverse leptin resistance in insulin resistant animals. Central dopaminergic activity may also be permissive or necessary for the known anti-diabetes effect of central leptin administration in mice lacking plasma insulin and this study therefore investigated the tenability of such a postu-late. Male C57BL/6J mice (10 wks old) were given 2 i.p. injections 4 days apart of STZ (120mg/kg) (N=40) to induce hyperglycemia (fasting plasma glucose [FPG] levels above 250 mg/dl) or vehicle (non-STZ) (N=6). STZ mice were subsequently divided into five groups and treated for 12 days as fol-lows: either STZ/icv vehicle [STZ/V], STZ/L1 or STZ/L2 [recombinant mouse

1882‑PLowering Blood Glucose Level Diminishes Brain Responses in Deci‑sion‑Making Areas while Promoting Food Desire in T2D PatientsWAI LAM, DONGJU SEO, CHRISTIAN SCHMIDT, SAMUEL ROSENBERG, MUHAMMAD HAMZA, LISA PARIKH, CHERYL LACADIE, JANICE J. HWANG, TODD CONSTABLE, RAJITA SINHA, ROBERT S. SHERWIN, RENATA BELFORT-DEAGUIAR, New Haven, CT

Glucose-responsive brain neural pathways sense energy homeostasis and control hunger and satiety, which are central to weight and diabetes man-agement. However, the impact of obesity and type 2 diabetes (T2D) on the interplay between neural regulatory mechanisms and appetite and eating behavior in these conditions remains unclear. To investigate the effects of hyperglycemia in T2D, we conducted BOLD fMRI studies to measure brain activity induced by food cues and collected food picture ratings during a 2-step hyper-euglycemic clamp in 24 subjects (age:47±7 years; BMI:33.5±3.2 kg/m2), comprised of 16 nondiabetic obese (OB) and 8 age-and BMI-matched participants with T2D (A1c=6.4±0.7%). During the fMRI scan, plasma glu-cose levels were raised to ~200 mg/dL for 30 minutes prior to the first BOLD fMRI and then lowered to ~95 mg/dL for the reminder of the scan. T2D and OB subjects showed different neural responses at varying plasma glucose levels. Greater activity in the left insula, striatum, and hippocampus, regions associated with hedonic control of eating behavior, (P=0.001) was found dur-ing hyperglycemia compared to euglycemia in the OB, but not in the T2D subjects. Compared to the OB group during euglycemia, T2D had higher hunger ratings (P=0.03) and lower ventromedial prefrontal cortex (vmPFC) activity that is linked to decision-making and regulating emotional behav-iors (P=0.001). Our data suggest that lowering blood glucose levels from hyperglycemia to euglycemia in chronically hyperglycemic T2D subjects provokes neural responses resembling a hypoglycemic state that result in the increased appetite observed in these T2D individuals. This indicates that the brain translates declines from hyperglycemia to euglycemia, often seen after meal, into desire and actions differently in individuals with and without T2D. These observations may help shed light on the neurobehavioral chal-lenges for glycemic control and weight reduction in patients with T2D.


1883‑P

WITHDRAWN

A500


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



ing glucose (8.6%, p=0.004), glucose tolerance test glucose area under the curve (AUC) (18%, p=0.023) and insulin AUC (47%, p=0.006) with a reduction in Matsuda insulin sensitivity index (56%, p=0.0007). This SuMN TH knock down significantly increased body weight gain (21%, p=0.003) while increas-ing feed efficiency (16%, p= 0.01) and food consumption (8%, p=0.01). Such knock down also reduced adipose tissue mitochondrial fatty acid oxidation (FAO) (basal oxygen consumption rate 29%, p< 0.0001; endogenous FAO rate 39%, p< 0.0001; and exogenous FAO 53%, p=0.029). Thus, selective knock down of SuMN TH expression induces insulin resistance/glucose intoler-ance as well as a shift in energy balance favoring body weight (fat) gain, likely via its direct and/or indirect communications with the SCN.

1888‑PThe Parasympathetic Nervous System Does Not Mediate Nutrient‑Induced Beta‑Cell ProliferationVALENTINE S. MOULLÉ, KEVIN VIVOT, JULIEN GHISLAIN, VINCENT POITOUT, Montreal, QC, Canada

In response to obesity-induced insulin resistance, pancreatic beta-cell mass and insulin secretion increase to maintain glucose homeostasis. Fail-ure of these compensatory mechanisms leads to type 2 diabetes. We have recently shown that simultaneous elevations of circulating glucose and fatty acid levels synergistically promote beta-cell proliferation in rats. However, whether nutrient-induced beta-cell proliferation is mediated by circulating or neural factors remains debated. The aim of this study was to assess the role of the parasympathetic nervous system (PNS) in beta-cell prolifera-tion in response to nutrients in rats. First, to assess the direct effects of nutrients in the brain on beta-cell proliferation, Lewis rats were infused with saline (SAL) or glucose and a lipid emulsion (20% Clinoleic) with hepa-rin (20 mU/ml) (GLU+CLI) towards the brain for 72 h, at a rate which does not alter circulating levels of glucose or fatty acids. Beta-cell proliferation, assessed by immunolabelling for Ki67 and insulin, was increased 2 fold in GLU+CLI-infused animals vs. SAL (p<0.05; n=5-6). Second, to determine the contribution of the PNS to nutrient-induced beta-cell proliferation rats were infused systemically with GLU+CLI to raise circulating levels of glucose and fatty acids, in the absence or presence of atropine (5 mg/kg) to block mus-carinic receptors or following celiac vagotomy. Beta-cell proliferation was increased 16 fold in response to systemic GLU+CLI infusion (p<0.001; n=5-6), and this proliferative response was maintained in the presence of atropine (n=5-6) or following vagotomy (n=4-5). These data show that although glu-cose and fatty acids can modestly induce beta-cell proliferation via a direct action on the brain, the PNS does not mediate the large beta-cell prolifera-tive response to elevated levels of circulating glucose and fatty acids.

1889‑PGlucagon‑Like Peptide‑1 (GLP‑1) Crosses the Blood‑Brain Barrier via Endothelial GLP‑1 Receptor‑Mediated ProcessZHUO FU, KEVIN AYLOR, ZHENQI LIU, Charlottesville, VA

GLP-1 in addition to regulating glucose-dependent insulin secretion exerts anorexic and neuroprotective effects. While brain-derived GLP-1 may par-ticipate in these central actions, evidence suggests that peripherally derived GLP-1 play an important role as well. Indeed, GLP-1 analog is able to cross the blood brain barrier (BBB) and exert central actions. How peripheral GLP-1 enters the brain remains unknown. Endothelium expresses abundant GLP-1 receptors (GLP-1 R) which may facilitate the trans-BBB transport of GLP-1.

We first examined GLP-1 R distribution and activation in the brain. Sys-temic infusion of GLP-1 significantly increased protein kinase A (PKA), a key signaling intermediate in the GLP-1 signaling pathway, activity (p<0.05) in hypothalamus, hippocampus, cerebellum, pituitary, cortex, and brain stem as well as brain microvessels. Systemic infusion of a labelled GLP-1 R ago-nist exendin-4-FAM led to 3-5-fold increase in fluorescence in all these brain regions (p<0.05), which was completely abolished by simultaneous infusion of GLP-1 R antagonist exendin 9-39. Brain microvessels expressed abundant GLP-1 R as well.

Both brain endothelial cells (RBECs) and astrocytes express abundant GLP-1 Rs. To examine the involvement of endothelial GLP-1 R in the GLP-1 transport process, RBECs were incubated with labelled GLP-1 (GLP-1-FAM) which showed that RBECs actively took up GLP-1-FAM and this action was blunted by either GLP-1 R antagonism or PKA inhibition. Using an artificially assembled BBB consisting of an endothelial layer and an astrocyte layer, we found that GLP-1-FAM time-dependently crossed the barrier from 5 min to 30 min and this was also blunted in the presence of GLP-1 R antagonist.

We conclude that GLP-1 is able to cross the BBB through active trans-endothelial transportation to act in the various regions of brain. This process

L continuously icv infused at doses 20ng/hr or 12ng/hr, respectively], STZ/ L1/DA antagonist [L icv infusion (20ng/hr) plus dopamine D1 and D2 receptor antagonists {SCH 23390, 1ng/hr; haloperidol 2ng/hr, continuous icv infu-sion}], or STZ/ L2/DB antagonist [leptin icv infusion (12ng/hr) plus dopamine D1 and D2 receptor antagonists {SCH 23390, 2ng/hr; haloperidol 4ng/hr}]. After 12 days of infusions, relative to non-STZ mice, STZ/V mice exhibited increased FPG by 2.7 fold (433±65 mg/dl vs. 160±5 mg/dl; p<0.001), and reduced plasma insulin by 72% (0.48±0.4ng/ml vs. 1.7±0.1 ng/ml; p<0.005). Both STZ/L1 and STZ/L2 treatment reversed such STZ induced hyperglyce-mia (to FPG of 128±7 or 188±22 mg/dl, respectively; p<0.001) without altering plasma insulin. However, compared to STZ/L1 and STZ/L2 treatment, STZ/L1/DA antagonist and STZ/L2/ DB antagonist treatments dose-dependently blocked 38% and 100% of the L effect on hyperglycemia (to FPG of 246±69 and 447±59mg/dl, respectively; p<0.001) without altering plasma insulin. The icv leptin effect to ameliorate diabetes in mice lacking insulin is likely either mediated or permitted by central dopaminergic neuronal activities.

1886‑PViral‑Mediated GK Knockout in Specific Hypothalamic Nuclei Con‑firms Differential Regulation of Pancreatic Islet PhysiologyWILFREDO ROSARIO, DAVID A. D’ALESSIO, CHRISTOPHER J. RHODES, Durham, NC, Gaithersburg, MD

A neuronal map capable of regulating islet physiology initiated by hypo-thalamic glucose sensing has been previously shown, closing a gap of more than 150 years.

Hypothesis: Hypothalamic glucose sensing by glucokinase (GK) directly regulates islet hormone physiology.

Methods: We performed stereotaxic AdV-Cre mediated GK KO, targeted to specific hypothalamic nuclei of male and female GKloxP mice. Intraperito-neal glucose and insulin tolerance tests were used to test the hypothalamic GK contribution to overall glycemia and islet hormone responses. Metabolic cages were used to assess hypothalamic GK contribution to feeding behav-ior and general metabolism.

Results and Conclusions: We show that Arcuate Nucleus glucose sens-ing via GK is required for proper insulin secretion, affecting systemic glu-cose levels. Additionally, GK glucose sensing in the Ventromedial Nucleus appears to affect glucose levels, without directly affecting insulin secretion; however, either insulin signaling, or hypoglycemia, instigates VMN to direct islet counterregulation (CRR) via glucagon secretion. Finally, GK glucose sensing in the Lateral Hypothalamic Area is responsible for setting systemic thresholding for glucostatic responses, particularly CRR, evidenced by low-ered overall glycemia in Cre-injected mice without direct effects on insulin secretion, yet marked glucagon responses that likely respond to the lowered glycemia. Further studies targeting the signaling pathways in individual cell types in these specific hypothalamic areas is warranted. In all of these stud-ies, adiposity was not altered in any of the Cre-injected mice. Metabolic cage analysis indicated no major changes in feeding responses and other parameters, suggesting the glucoregulatory effects of hypothalamic regula-tion of islet hormone secretion are complementary to islet glucose sensing, with specific physiologic responses controlled by specific compartments of the hypothalamus.


1887‑PSelective Inhibition of Supramammillary Nucleus (SuMN) Dopami‑nergic Neuronal Activity Induces Insulin Resistance and ObesityYAHONG ZHANG, TSUNG HUANG TSAI, MICHAEL EZROKHI, SCOTT WATTERS, CHRISTINE CARDI, ANTHONY H. CINCOTTA, Tiverton, RI

The SuMN has recently been identified as a novel brain center regulating peripheral fuel metabolism. Inhibition of global SuMN neuronal activity with local infusion of an inhibitory cocktail (GABAA agonist/NMDA antagonist/AMPA antagonist) induces metabolic syndrome. The SuMN contains dopa-minergic neurons that directly and indirectly project to the suprachiasmatic nuclei (SCN), that in turn is a major regulator of metabolism. In high fat diet (HFD)-induced obese insulin resistant animals, the circadian peak activity of these SuMN dopamine neurons is reduced concurrently with a reduction of the circadian peak dopamine activity at the clock region. This study there-fore investigated the possible regulatory effect of SuMN dopamine neurons on peripheral metabolism by in vivo knock down of tyrosine hydroxylase (TH, the rate-limiting enzyme for dopamine synthesis) expression at the SuMN using AAV-mediated shRNA targeting TH (AAV-TH shRNA). HFD-resistant rats were micro-infused at the SuMN with either AAV-TH shRNA (N=24) or AAV-scrambled shRNA [control] (N=18) while maintained on HFD for 37 days. Compared with control rats, SuMN TH knock down rats had increased fast-

A501


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


INTEGRATED PHYSIOLOGY—INSULIN SECRETION IN VIVO

ing, iAUC, 120’, 180’), and fasting insulin levels (p=<0.001), and increased BCGS by 146% (p=0.01). EX9 had no effect on GPE; lowered insulin response to oral glucose (iAUC) by 54% (p=<0.001); reversed the improvement in BCGS to pre-GBP levels (pre-GBP: 0.42 vs. post-GBP+EX9: 0.58 pmol·kg-1·min-1 mM-1, p=ns). The response to EX9 after GBP was highly variable and overall relatively mild. EX9 significant increased 180’ glucose levels by ~25% com-pared to saline after GBP (p=0.001).

Conclusions: GBP weight loss results in significant improvement of β-cell function and glucose in individuals with DM2. Blocking the effect of endog-enous GLP-1 reversed the GBP-related improvement in BCGS, suppresses insulin secretion to oral glucose, and worsened, albeit minimally, post-pran-dial glucose tolerance.

Supported By: National Institute of Diabetes and Digestive and Kidney Dis-eases; National Institutes of Health

& 1892‑PAbnormal Glycemic Control in East Asians with Prediabetes Is Largely due to Defects in Beta‑Cell Function Rather than Peripheral Insulin ResistanceFAIDON MAGKOS, MICHELLE H. LEE, MAYBRITTE J.W. LIM, YONG MONG BEE, KEE SENG CHIA, DAPHNE S. GARDNER, JEFFREY HALTER, SHIH LING KAO, ERIC Y. KHOO, SU CHI LIM, TZE PING LOH, LINDA W.L. TAN, ROB M. VAN DAM, TONG WEI YEW, CHIN MENG KHOO, SUE-ANNE TOH, Singapore, Singapore, Ann Arbor, MI

The pathophysiology of type 2 diabetes involves peripheral insulin resis-tance and β cell dysfunction, but the relative importance of each in abnor-mal glucose homeostasis remains controversial. We studied 65 prediabetic subjects (classified by ADA criteria) and 65 normal subjects of East Asian descent. The two groups had similar BMI (23.2 vs. 22.3 kg/m2, p=0.080), age (51.7 vs. 49.8 years, p=0.189) and sex distribution (54% male, 46% female). Each subject underwent a 75g oral glucose tolerance test, a 10min IV glu-cose tolerance test to determine acute insulin response to glucose (AIR, cal-culated from incremental area-under-the-curve for insulin concentrations), and a 3h euglycemic-hyperinsulinemic clamp to determine glucose disposal (M-value). Compared to normal subjects, prediabetics had greater mean fasting glucose concentration (5.2 vs. 4.8 mmol/L, p<0.001), 2 h post-prandial glucose (7.0 vs. 5.6 mmol/L, p<0.001), incremental area under the glucose curve (398 vs. 290 mmol/L · min; p<0.001) and HbA1c (5.8 vs. 5.3%, p<0.001). Insulin sensitivity (M-value, normalized to fat free mass) was slightly (~14%) but significantly lower in the prediabetic compared to the normal group (14.1 vs. 16.3, p=0.006). Insulin secretion was impaired to a much greater extent, with prediabetics having ~34% lower AIR than normal subjects (549 vs. 832 mU/L · min, p=0.012). Consequently, the prediabetic group had a ~42% lower disposition index (AIR x M value): 7394 vs. 12694, p=0.001 than the normal group, consistent with worse β cell function.

In summary: 1) absolute insulin secretion in response to a glucose load is diminished in prediabetic subjects of East Asian descent. 2) there is a lack of β cell compensatory response to the prevailing decrease in insulin sensitivity in this population. The % reduction of disposition index suggests that β-cell dysfunction rather than insulin resistance is the primary defect in East Asians with prediabetes.

Supported By: Janssen Pharmaceuticals; National Medical Research Council of Singapore; Singapore Ministry of Health; National University Health System, Singapore

& 1893‑PBeta‑Cell Dysfunction and Amplified Insulin Demand Increase the Proinsulin/Insulin Ratio in HumansTERESA MEZZA, VINSIN A. SUN, SIMONA MOFFA, CHIARA M.A. CEFALO, SER-GIO ALFIERI, FRANCESCA CINTI, ALEX BROCCHI, GIUSEPPE QUERO, FRANCO FOLLI, ANDREA MARI, ANDREA GIACCARI, Rome, Italy, Milan, Italy, Padova, Italy

Increased proinsulin secretion, found in type 2 diabetes and insulin-resis-tance, may be due to an intrinsic, primitive defect in proinsulin processing, or be secondary to increased demand on β-cells(hyperinsulinemia secondary to insulin-resistance). An alternative way to address the relation between relative hyperproinsulinemia and increased secretory demand is to study the dynamic changes in proinsulin to insulin ratio (P/I ratio) after partial pancre-atectomy (PP). To examine dynamic changes of in-vivo insulin secretion (IS), beta-cell function and proinsulin secretion, 9 nondiabetic patients (6F/3M, 55.3±7.08 yrs., BMI 27.2±1.48 kg/m2), scheduled for PP, underwent 4-hour mixed meal test (MMT) and hyperinsulinemic euglycemic clamp (HEC) pre- and post PP surgery. B-cell glucose sensitivity (GS) was calculated as ratio of IS and glucose increments during MMT. Glucose, Insulin, C-peptide and pro-insulin levels were measured every 30 min over 4-hour MMT. Following PP, basal IS rate (85.3±10.3 vs. 57.7±7.59 pmol·min-1·m-2, p=0.04), total IS rate

involves endothelial GLP-1 R binding and activation and may explain the cen-tral effects of GLP-1 R agonists.

Supported By: American Diabetes Association (1-16-PDF-037 to Z.F.); National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Dis-eases (1K01DK107731-01A1)


Moderated Poster Discussion: Integrated Physiology—Insulin Secre-tion In Vivo (Posters: 1890-P to 1895-P), see page 16.

& 1890‑PEffect of Vitamin D Supplementation on Insulin Resistance and β‑Cell Function in Prediabetes: A Double‑Blind, Randomised, Pla‑cebo‑Controlled TrialHELEN J. WALLACE, LAUREN HOLMES, CIERAN N. ENNIS, CHRISTOPHER CARDWELL, JAYNE V. WOODSIDE, IAN S. YOUNG, PATRICK M. BELL, STEVEN J. HUNTER, MICHELLE C. MCKINLEY, Belfast, United Kingdom

Low serum 25-hydroxyvitamin D (25(OH)D) concentrations are associated with insulin resistance, β cell dysfunction and type 2 diabetes. We inves-tigated the effect of vitamin D supplementation on insulin resistance and β cell function in subjects with prediabetes and low serum 25(OH)D concen-trations. Participants were randomised to receive 3000IU(75μg) cholecalcif-erol or placebo daily for 26 weeks. Compliance was monitored by pill count and change in serum 25(OH)D concentration using ultra performance liquid chromatography. The primary endpoint was between-group difference in change in insulin resistance assessed using a two-step euglycaemic-hyper-insulinaemic clamp technique combined with infusion of tritiated glucose. An oral glucose tolerance test was performed pre- and post-intervention to calculate indices of β cell function. Between group comparisons were made using analysis of covariance (ANCOVA). 64 participants completed the study. Baseline serum 25(OH)D in the vitamin D and placebo group was 30.7 and 30.0nmol/l with serum 25(OH)D concentration increasing by 70.5nmol/l and 5.3nmol/l respectively after supplementation (p<0.001). There was no dif-ference between groups in measures of whole-body, peripheral or hepatic insulin resistance. Exogenous glucose infusion rate step 2 (p=0.94), whole body glucose uptake (Rd) step 2 (p=0.92), endogenous glucose production basal (p=0.27), step 1 (p=0.44). No difference was found between groups in measures of β cell function: HOMA-β (p=0.46), Stumvoll (p=0.32), first phase insulin secretion (p=0.77), second phase insulin secretion (p=0.70) and insulinogenic index (p=0.22). Optimisation of Vitamin D status had no effect on insulin resistance or β cell function in people with prediabetes and low 25(OH)D.

Supported By: Northern Ireland HSC and R&D Division; Northern Ireland Chest, Heart and Stroke; Metabolic Unit Research Fund; Royal Victoria Hospital, Belfast

& 1891‑PRole of GLP‑1 in the Recovery of β‑Cell Glucose Sensitivity in DM2 after Gastric BypassANKIT M. SHAH, BETSY ROJAS, MICHAEL AHLERS, KIARRA LEVESQUE, FATIMA ALAM, ESMERALDA PIERINI, MARLENA HOLTER, JOHN HARVEY, NINAN KOSHY, KOJI PARK, SAURABH SHARMA, JAMES MCGINTY, JR., BLANDINE B. LAFERRÈRE, New York, NY

Background: About 60% of patients experience type 2 diabetes (DM2) remission after gastric bypass surgery (GBP). Enhanced post-prandial secre-tion of glucagon-like peptide-1 (GLP-1) is thought to mediate the glycemic improvement after GBP. The exact contribution of GLP-1 has not been fully elucidated.

Hypothesis: The improvement in β-cell glucose sensitivity (BCGS) to oral glucose occurs rapidly after GBP, is mediated by endogenous GLP-1 and can be blocked by exendin9-39 (EX9), a competitive GLP-1 receptor antagonist.

Methods: 15 individuals with DM2 underwent a 75 g oral glucose test prior to and 3 months after GBP. Glucose levels, insulin secretion rates (ISR) by C-peptide deconvolution, and BCGS, or the slope between ISR and cor-responding glycemia, were measured with and without EX9. Acetaminophen 1500 mg was used to assess gastric/pouch emptying (GPE).

Results: Prior to GBP: age 42.6±8.1 years, weight 112.2±20.9 kg, BMI 42.9±5.1 kg/m2, DM2 duration 8.1±6.2 years, HbA1c 7.9±1.3%, HOMA-IR 12.3±7.8 and 43% of subjects were on insulin. Three months after GBP, weight loss was 18.5±5.4 kg, HbA1c 6.4±1.3%, and HOMA-IR 3.9±2.8. GBP significantly shortened GPE by 45% (p=0.03), decreased glucose levels (fast-

A502


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



286±11 at w6-HFD) with RDN during the acute phase of IV test. We for the first time demonstrate that bilateral RDN restores HFD impaired hepatic SI mainly by improving insulin secretion in response to glucose and enhancing β cell function. It is important to explore the inter-organ crosstalk between renal SNS, pancreas and liver as therapeutic potential for diabetes.

1896‑PIL‑6‑Type Cytokine Signaling in Adipocytes Induces GLP‑1 SecretionSTEPHAN WUEEST, CÉLINE I. LAESSER, MARIANNE BÖNI-SCHNETZLER, FLURIN ITEM, FABRIZIO C. LUCCHINI, WERNER MÜLLER, MARC Y. DONATH, DANIEL KONRAD, Zürich, Switzerland, Basel, Switzerland, Manchester, United Kingdom

Using adipocyte-specific glycoprotein 130 (gp130) knockout mice we recently showed that IL-6-type cytokine signaling in adipocytes induces FFA release from visceral adipocytes thereby promoting obesity-induced hepatic insulin resistance and steatosis. In addition, IL-6-type cytokines may increase the release of leptin from adipocytes, thereby inducing GLP-1 secretion and, thus potentially improving β-cell function. Herein, we aimed to test the possible role of adipose IL-6-type cytokine signaling in the regula-tion of insulin secretion.

Adipocyte-specific gp130 knockout mice on a high fat diet for 12 weeks showed impaired oral and intra-peritoneal glucose tolerance when com-pared to control littermates. In addition, circulating leptin, insulin and GLP-1 levels were reduced. In line with such finding, intestinal expression of PCSK1, the gene encoding PC1/3, which controls GLP-1 production, was decreased in knockout mice. Importantly, the GLP-1 receptor antagonist exendin 9-39 blunted impaired glucose tolerance in adipocyte-specific gp130 knockout mice. Ex vivo, glucose and GLP-1 stimulated insulin secretion was not affected in islets of knockout mice, further suggesting that an impaired incretin function constitutes the observed metabolic phenotype. Taken together, adipocyte-specific IL-6 signaling induces GLP-1 release in obesity to enhance insulin release thereby counteracting insulin resistance.

Supported By: Bangerter-Rhyner Foundation

1897‑PA Novel Measure of the Loss of Glucose HomeostasisDANIEL KEENAN, ANANDA BASU, JOHANNES VELDHUIS, RITA BASU, Charlottesville, VA, Rochester, MN

Regulation of metabolic homeostasis occurs at the level of the rates of production (glucose) and secretion (insulin, glucagon). A new methodology for detecting a loss of homeostasis is proposed that avoids many of the difficulties encountered in the conventional estimation of insulin-glucose sensitivity or resistance, while wholly incorporating the dynamics of key co-regulators. In a nocturnal study, healthy subjects without diabetes (ND, N=20) and subjects with T2D (N=21) were investigated by repeated over-night blood sampling of glucose, insulin and glucagon concentrations. The secretion rates were recovered by deconvolution. Under homeostasis, the joint time-evolving 3-dimensional secretory patterns of glucose, insulin and glucagon should not meander, but, over time, be “pulled-back” towards equi-librium. This is quantified via the volume of the convex hull of its 3D time-evolving secretory pattern (Figure a). The method strongly separates the two groups (Figure b). The homeostasis model was also applied to fed state data (76 subjects, classified by FG and GT tests). The method was able to delin-eate, within NFG, between those with normal and impaired glucose toler-ance (Figure c). In both studies, subjects (marked as diamonds in Figure b-c) were identified for further examination as early-stage diabetes candidates. This new procedure should have utility as an alternative or as a supplement to existing early-stage detection methods.

Figures.

(69.6±10.9 vs. 34.0±4.43 nmol·m-2, p=0.01) and GS (187±46.1 vs. 51.7±18.7 pmol·min-1 ·m-2·mM-1, p<0.01) decreased significantly. Fold change in P/I ratio significantly increased over time following PP (p<0.05). When sub-jects were classified as insulin-sensitive or resistant (using median glu-cose uptake during HEC [5.4 mg·kg-1·min-2] as cut-off), P/I ratio was similar between groups at baseline. However, after PP, insulin-sensitive subjects showed no significant change in P/I ratio over time (AUC P/I Ratio 48.5±10.4 vs. 47.9±10.8; p=0.33), while insulin-resistant showed significant increase in P/I ratio over 4-hour MMT (AUC P/I Ratio 55.9±16.4 vs. 78.12±21.1; p=0.01). Our data suggest that insulin-resistance is associated with increased P/I ratio and that this ratio is further amplified in presence of increased demand for insulin secretion, therefore confirming its role as a marker of dysregu-lated insulin secretion.

Supported By: European Foundation for the Study of Diabetes

& 1894‑PComprehensive Analysis to Reveal Physiological Role of O‑GlcNAc‑ylation in Glucose Metabolism by Using Tissue‑Specific Ogt Knock‑out MiceSHOGO IDA, KATSUTARO MORINO, OSAMU SEKINE, NATSUKO OHASHI, SHINJI KUME, KANAKO IWASAKI, NORIO HARADA, NOBUYA INAGAKI, SATOSHI UGI, HIROSHI MAEGAWA, Otsu, Japan, Kyoto, Japan

Post-translational modifications to intracellular proteins regulate a variety of cellular functions. Growing evidence indicates that dysfunction of post-translational modifications disrupts cellular homeostasis and is strongly associated with the pathogenesis of numerous diseases. O-GlcNAcylation is one of the post-translational modification that is characterized by the addition of Nacetylglucosamine to various proteins by O-GlcNAc transferase (Ogt), and it serves as “a nutrient sensor” that can regulate diverse cellular processes in response to nutritional status. Although it has been speculated that O-GlcNAcylation is associated with glucose metabolism, its role in whole body glucose metabolism has not yet been fully clarified. In this study, to reveal the physiological role of O-GlcNAcylation in glucose metabolism, tamoxifen-inducible global Ogt-KO mice (Ogt-KO) were analyzed. In addition, mice lacking the Ogt gene in glucose metabolism-related tissues, including the liver, skeletal muscle, adipose tissues and pancreatic β cells, were ana-lyzed. Ogt-KO showed a lethal phenotype with hypoglycemia, suggesting that O-GlcNAcylation is essential for survival in adult mice. Furthermore, tissue-specific Ogt deletion from insulin target organs, including liver, skel-etal muscle and adipose tissues, had little impact on glucose metabolism in physiological condition. However, pancreatic β cell-specific Ogt knockout mice exhibited transient hypoglycemia associated with enhanced insulin secretion and accelerated adiposity, followed by subsequent hyperglycemia with insulin depletion accompanied by β cell apoptosis with enhanced ER stress. These findings suggest that O-GlcNAcylation does not impact glu-cose metabolism in insulin target organs but plays crucial roles in pancreatic β cell function and survival. Our results provide novel insight into O-GlcNAc biology and physiology in glucose metabolism.

Supported By: Japan Society for the Promotion of Science

& 1895‑PRenal Denervation Improves Hepatic Insulin Sensitivity by Improv‑ing β‑Cell Function in Fat‑Fed DogsMALINI S. IYER, ORISON O. WOOLCOTT, JEREMY E. KORMAN, FRANCESCA PIC-CININI, CATHRYN M. KOLKA, RICHARD N. BERGMAN, Los Angeles, CA

Over-activation of the sympathetic nervous system (SNS) has been asso-ciated with metabolic disorders. We have previously shown that inhibiting SNS by surgical renal denervation (RDN) improves insulin sensitivity (SI) despite basal hyperinsulinemia in the obese dog model. We hypothesized that RDN improves SI by decreasing insulin clearance and enhancing β cell function. Direct evidence for these latter two mechanisms after RDN is lack-ing. In dogs fed on a high-fat diet for 6wks (w6-HFD) bilateral RDN (n=8) was performed by stripping all visible nerves enwrapping the renal artery and painting the artery with 10% phenol. Sham surgery (SS, no RDN) was per-formed on 7 additional animals. RDN compared to Sham totally restored HFD impaired hepatic SI to pre-fat w0 levels ((x 10-4 dl kg-1 min-1 pM-1): 0.5±0.3 at w6-HFD vs. 1.8±0.3 at HFD+RDN, P<0.001; 1.6±0.3 at w0) but did not restore extra-hepatic peripheral SI. Also RDN potentiated the acute insulin response to glucose (AIRg (mu.l-1.min), RDN:3237±298 at HFD+RDN vs. 2731±109 at w6-HFD, P<0.01, 2659±237 at w0, P<0.05 vs. HFD+RDN; SS: 2602±545 at HFD+SS, 3657±419 at w6-HFD and 2717±401 at w0, P=ns). We also found increased C-peptide AUC (56.7±4.4 at HFD+RDN vs. 46.6±2.3 at w6-HFD, P<0.01; 61.44±3.3 at HFD+SS vs. 58.3±5.1 at w6-HFD and insulin secretion rates (ISR, 256±23 at HFD+RDN vs. 222±2 at w6-HFD; 289±6 at HFD+SS vs.

A503


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



gery, p<0.01), incremental first phase, (- 58%, p<0.01) second phase, (- 33%, p<0.04) as well as in arginine-stimulated insulin secretion (1919±330.5 before surgery vs. 648.7±244.1 pmol/L after surgery, p=0.01). GS was reduced by 38% during HC and by 78% during MMT. Consequently, the incre-tin effect also decreased significantly following PD (2.87±0.47 before sur-gery vs. 1.11±0.17 after surgery, p<0.01). These data suggest that acute beta-cell loss determines not only quantitative, but also qualitative alterations of residual beta-cell mass. Further, impaired β-cell GS during MTT following PD may be driven by the decreased incretin effect. The previously observed increased GLP-1 secretion following PD does not seem to fully compensate for the reduced incretin effect. Our data are in favor of a pivotal role of the incretin effect (even more than incretin concentration) on the dysregulation of β-cell responsiveness.


1900‑PPancreatic Fat Accumulation Is Associated with Decreased β‑Cell Function and Deteriorated Glucose ToleranceYOU CHEOL HWANG, IN JIN CHO, IN KYUNG JEONG, KYU JEUNG AHN, HO YEON CHUNG, Seoul, Republic of Korea

Non-adipose tissue ectopic fat accumulation is reported to be associated with insulin resistance and cellular dysfunction. Insulin secretory capacity is reported to be lower in Asians compared with Caucasians. We aimed to investigate the association between pancreatic fat accumulation and insulin secretory capacity and glucose tolerance in Korean adults. A total of 39 indi-viduals (aged 49.9 ± 10.9 years, 53% males) without history of diabetes melli-tus were recruited. Participants were stratified by the results of oral glucose tolerance test (OGTT); normal glucose tolerance (NGT, n=8), prediabetes (impaired fasting glucose and/or impaired glucose tolerance, n=13), and dia-betes mellitus (DM, n=18), and plasma insulin levels were determined at 0, 30, 60, 90, and 120 min. All participants were performed proton magnetic resonance spectroscopy to assess pancreatic fat amount and insulin sensi-tivity and β-cell function were measured by frequently sampled intravenous glucose tolerance tests (FSIVGTT) and OGTT-derived indices. As glucose tolerance worsened from NGT to prediabetes and DM, parameters reflect-ing pancreatic β-cell function, including homeostatic model assessment-β (HOMA-β), insulinogenic index, acute insulin response to glucose (AIRg), and disposition index (DI), were decreased (P<0.05), whereas insulin sensitivity indices, including HOMA-insulin resistance, Matsuda index, Stumvoll index, and insulin sensitivity (Si), were not different between the groups. Pancre-atic fat contents increased with the deterioration of glucose tolerance (NGT: 12.0%, prediabetes: 23.7%, and DM: 31.9%, P<0.05). Pancreatic fat content was negatively correlated with AIRg and DI, but not with Si derived from FSIVGTT.

In conclusion, increased pancreatic fat accumulation is associated with decreased insulin secretory capacity and which may contribute to the dete-rioration in glucose tolerance in Korean adults.

Supported By: Korean Diabetes Association

1901‑PSerum ZnT8 Level in Type 2 Diabetes, LADA, and PrediabetesEMANUELA ZAHARIEVA, ZDRAVKO KAMENOV, TSVETELINA VELIKOVA, Sofia, Bulgaria

ZnT8 is a trans-membrane protein expressed in insulin-containing secre-tory granules of beta cells. It is explored in two major aspects - it is a major autoantigen in type 1 diabetes and polymorphisms in the encoding SLC30A8 gene are associated with altered risk of type 2 diabetes mellitus (T2D). Little is known about its serum levels in prediabetic state and diabetes. Serum level of ZnT8 was assayed through ELISA in 140 patients with diabetes (113 with T2D and 27 with latent autoimmune diabetes of the adults - LADA), 51 subjects with prediabetes and 38 controls. The level was significantly higher in prediabetic group (428.53 ± 304.99 pg/ml), followed by T2D (323.96±252.19 pg/ml) and the lowest in controls (112.67 ± 56.01 pg/ml), p<0.05. ZnT8 level was higher in T2D compared to LADA (206.95 ± 206.90 pg/ml), p=0.005. The latter did not differ significantly from controls, p=0.22. Within both T2D and LADA patients but not the control group we observed a positive cor-relation with BMI, waist circumference, VLDL cholesterol and triglycerides level and a negative one for HDL cholesterol (p<0.05). Plasma glucose and HbA1c did not correlate with ZnT8 level among diabetic patients (p>0.05). The correlation with BMI was present also in prediabetes group (Spearman’s rho=0.300, p= 0.033). Analysis among diabetics with BMI<25kg/m^2 did not confirm correlations with BMI and glucose level but those with lipids were persistent (p<0.05). Serum ZnT8 level correlated positively with hs-CRP in T2D patients (Spearman’s rho=0.205, p=0.048).

Supported By: National Institutes of Health (R01DK29953)

1898‑PLow Lp(a) Is Related to β‑Cell Dysfunction, Insulin Resistance, and Right‑Handedness in T2DMMICHEL P. HERMANS, SYLVIE A. AHN, MICHEL F. ROUSSEAU, Brussels, Belgium

Lipoprotein(a) is the strongest genetic risk factor for CVD. By contrast, low Lp(a) confers decreased risk of incident T2DM. While it is established that low on-statin LDL-C impairs B-cell secretion, it is not known whether such an association exists regarding Lp(a). The cardiometabolic phenotype of 553 T2DM Caucasians (mean (SD) age: 68 (12) years; 61% males; diabe-tes duration 17 (9) years)) was determined according to Lp(a): a low-Lp(a) group (1st Lp(a) quartile [QI] (n=138; mean Lp(a): 6 nmol/L) was compared to a moderate-to-high Lp(a) group ([QII-IV] (n=415); mean Lp(a) 73 nmol/L). Insulin sensitivity [S]; β-cell function adjusted for [S] (hyperbolic product between B-cell function and insulin sensitivity [BxS]), and annual [BxS] loss rate were determined by HOMA. The 2 groups did not differ in age; gender; BMI; MetS; BP; glucose-lowering and CV drugs; HbA1c; LDL-C or apolipoprotein B100. Low-Lp(a) patients were younger at diabetes diagnosis: 49 (12) years vs. 52 (12) years (p 0.0112). Low-Lp(a) patients had lower insulin sensitivity (47 (34)% vs. 58 (41)%; p 0.0020); lesser [BxS] (25 (18)% vs. 29 (19)%; p 0.0291); and higher [BxS] loss rate (1.40 (0.60)%/year vs. 1.29 (0.50)%/year; p 0.0340) than [QII-IV]. Overall macroangiopathy was 26% in [QI] vs. 37% in [QII-IV] (p 0.0226). There was no difference between groups in overall microangi-opathy: 55% vs. 46% (NS). Non-right-handedness was much more frequent in [QII-IV] patients: 14% vs. 5% in low-Lp(a) (p 0.0024). Plasma Lp(a) levels were modulated by laterality, being much higher (+71% median value) in non-right-handed patients (n=66; 12%): 73.1 (95.4) nmol/L (median [IQR] 41.0 [12.1-85.4] nmol/L) vs. 52.8 (71.4) nmol/L (median 24.0 [10.0-71.8] nmol/L) in right-handed patients (n=479; i.e., 88%) (p 0.0145). Low plasma Lp(a) levels are linked to both insulin resistance and greater β-cell function loss, with earlier onset of T2DM. Beyond the expected association with all-cause CVD, higher plasma Lp(a) levels are also associated with left-handedness.

1899‑PSurgical Acute Beta‑Cell Loss Determines Beta‑Cell Dysfunction and Reduced Incretin Effect in HumansTERESA MEZZA, FRANCESCA CINTI, VINSIN A. SUN, CHIARA M.A. CEFALO, GIAN PIO SORICE, ILARIA TORTORELLI, SIMONA MOFFA, SERGIO ALFIERI, ANDREA MARI, ANDREA GIACCARI, Rome, Italy, Padova, Italy

Pancreaticoduodenectomy (PD) causes acute β-cell loss (~50%) and a compensatory increase in GLP-1 secretion. In this study we explored the effects of PD on quantitative and qualitative parameters of insulin secre-tion. We studied insulin secretion, β-cell glucose sensitivity (GS) and incretin effect in 13 nondiabetic patients, (10 F/8 M, 51±15 yrs., BMI 27.9±5.3 kg/m2), before and after PD, using a 2-h hyperglycemic clamp (HC) + arginine and a mixed meal test (MMT). GS was calculated as the ratio of insulin secretion and glucose increments (HC) or modeling (MTT). Incretin effect was esti-mated as the ratio of GS during MTT and HC. As expected, PD caused a significant reduction in total insulin secretion rate, (77.3±6.68 before surgery vs. 37.3±4.90 nmol·m-2 after surgery, nmol·m-2, p<0.001), basal insulin secre-tion rate, (101±9.82 before surgery vs. 60.2±6.62 pmol·min-1·m-2 after sur-

A504


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



pmol·min-1·m-2, p=0.05) and in GS (34.4±11.3 vs.13.1±6.13 pmol·min-1·m-2mM-1, p=0.01). In this study the acute beta-cell mass reduction had a different impact on insulin secretory capacity, despite comparable functional mass at baseline, according to pre-surgery insulin secretion characteristics. This suggests that underlying beta-cell dysfunction anticipates the decline of beta-cell responses, being the pivotal mechanism for the development of hyperglycemia.


1904‑PE2F1 Controls Pancreatic Beta‑Cell Plasticity and Function through GLP‑1 SignalingXAVIER GROMADA, NABIL RABHI, CHARLÈNE CARNEY, JULIE A. KERR-CONTE, FRANÇOIS PATTOU, PHILIPPE FROGUEL, JEAN SÉBASTIEN ANNICOTTE, Lille, France

Loss of β cell-specific traits has been proposed as a cause of β cell failure during type 2 diabetes (T2D) development, but the molecular mechanisms remain unclear. Here, we identified an important role for the cell cycle regu-lator E2F1 in the control of a regulatory gene network essential for main-taining the functional and molecular traits of mature β cells. Conditional E2F1 inactivation in β cells (E2F1β-/-) caused glucose intolerance and hypo-insulinemia associated with altered islet morphology. Immunofluorescence assays demonstrated an increase of α-cell number in E2F1-deficient islets, suggesting a molecular link between E2F1 and β-cell identity. Since E2F1 lev-els are reduced in human T2D islets, we suggest that E2F1 could represent a key transcription factor necessary to maintain β-cell identity.

Since Glucagon-like peptide-1 receptor (GLP-1 R) deficient mice also have altered islet morphology (Z Ling, et al, 2001), as observed for E2F1-deficient islets, we hypothesized that E2F1 could play a critical role in mediating the GLP-1 effects in β cells. Compared to control mice, oral glucose tolerance tests (OGTT) demonstrated that E2F1β-/- mice are intolerant to glucose. Con-versely, mice overexpressing hE2F1 specifically in β cells have improved tol-erance to glucose during OGTT, suggesting that the GLP-1 pathway may be affected by E2F1. These metabolic alterations are linked to variation in GLP-1 R expression in pancreatic islets of these mice. Bioinformatic analysis of the GLP-1 R promoter further revealed the presence of an E2F1 DNA-binding site. Chromatin immunoprecipitation demonstrated differential epigenetic regu-lation of the GLP-1 R promoter in E2F1 absence. Finally, treatment of human islets with an E2F inhibitor led to an increased α-cell number, associated to decreased GLP-1 R expression.

Altogether our data suggest that E2F1 could be a crucial transcription fac-tor necessary to maintain β-cell function and identity through the control of β-cell gene markers including GLP-1 R levels.

Supported By: Agence Nationale pour la Recherche; Société Francophone du Diabète Association pour la Recherche sur le Diabète Nord Pas de Calais Regional Council; Lille 2 University

1905‑PPathogenic Mechanisms of Prediabetes in Obese and Very Obese African‑American Women: Implications for Primary Diabetes PreventionKWAME OSEI, TRUDY R. GAILLARD, Columbus, OH, Cincinnati, OH

Background: Prediabetes is a very heterogeneous disorder that pre-cedes type 2 diabetes (T2DM). Metabolic predictors of prediabetes include impaired beta cell secretion (AIRg), insulin sensitivity (Si) and glucose effec-tiveness (Sg). However, the degree to which obesity per se influences pre-diabetes in ethnic populations remains controversial. Thus, we investigated whether the pathogenic mechanisms differ in obese (OB, BMI<35) and very obese (VOB, BMI>35) African American women (AAW) with prediabetes.

Subjects and Methods: We recruited 26 OB and 41 VOB AAW with pre-diabetes, mean age (46.3±10.3 years), A1c (5.9±0.4%) and BMI (38.3±8.2 kg/m2). OGTT and FSIVGT were performed in each subject. Body composition (% body fat) was measured using DEXA. Si, AIRg, Sg and disposition index (DI) =AIRg x Si) were calculated using minimal model method.

Results: Mean BMI (32.6±1.9 vs. 42.8±5.5 kg/m2) and body fat (44.7±2.0 vs. 49.6±2.2%) were significantly (p=0.0001) lower in OB vs. VOB. Mean AIC was not different among our groups. Mean fasting and post-glucose serum glucose, insulin and c-peptide levels were significantly (p=0.03-0.0001) lower in OB vs. VOB subjects. Mean AIRg was not statistically different in OB vs. VOB (808±776 vs. 535±443 (x min [μU/L]−1), p=0.106). Similarly, Sg (2.05±1.81 vs. 1.79, (× 10−2/min), p=0.53) was not different. However, mean DI was greater in OB than VOB (1999±1408 vs. 1511±1033, p=0.01).

Conclusion: Compared with OB, VOB was associated with identical Si and Sg, but attenuated AIRg and DI in AAW with prediabetes. These pathogenic

In conclusion, ZnT8 level is associated with factors used in assessment of the metabolic syndrome. We observe increased levels prior to develop-ment of T2D and a decrease after diagnosis, but they still remain higher than that in LADA. Analysis in conjunction with insulin secretion and sensitivity would further elucidate the potential of ZnT8 to contribute to biomarkers of endocrine pancreas function and progress of insulin resistance syndrome.

Supported By: Sanofi Bulgaria

1902‑PThe Short‑Term Effect of Roux‑en‑Y Gastric Bypass and Sleeve Gas‑trectomy on Functional Beta‑Cell Mass: A Randomized, Controlled Clamp StudyMATTHIAS LANNOO, CHANTAL MATHIEU, STEFFEN FIEUWS, ANN MERTENS, ANDRÉ D’HOORE, BART VAN DER SCHUEREN, Leuven, Belgium

Type 2 diabetes (T2D) is known to improve after gastric bypass (RYGB) sur-gery and sleeve gastrectomy (SG). Nonetheless, it remains unclear whether this improvement is solely due to a fall in insulin resistance together with a recovery of the incretin effect or whether the functional beta-cell mass increases. We conducted a randomized study with 30 patients with T2D being assigned to either a surgical intervention, RYGB or SG followed by a protein sparing modified fast (PSMF), or to 3-weeks of PSMF alone. Patients underwent a hyper-glycemic clamp procedure at baseline and after the 3 weeks. From plasma c-peptide levels during the hyperglycemic clamp, the AUCs and insulin secretion rates (ISR) at baseline and during the three phases (first, second and third phase) of the clamp were calculated to assess the functional beta-cell mass. Data are presented as means ± SD. Variables are compared between groups using a Kruskal-Wallis test followed by pair-wise Mann-Whitney U tests. Results are given in Table 1. AUCs C-peptide and ISRs were higher after SG and RYGB than after 3 weeks of PSMF in all phases of the clamps though the result is mostly driven by the patients who underwent SG. Thus our study results suggest that functional beta-cell mass improves after RYGB and SG, but not after PSMF alone.

Table 1. AUC C-Peptide (pmol/L/min) and ISR (pmol/kg/min) after 3 Weeks of PSMF or RYGB/SG + PSMF.

PSMF N=10 RYGB N=10 SG N=10 P‑value 1 vs. 2 1 vs. 3 2 vs. 3AUC c‑pep Baseline 486.2 ± 177.56 750.4 ± 334.02 770.9 ± 262.95 0.056 0.104 0.017 0.910AUC c‑pep Phase 1 516.5 ± 166.1 902.3 ± 166.1 978.2 ± 166.1 0.011 0.038 0.004 0.623AUC c‑pep Phase 2 1016.6 ± 254.6 1739.1 ± 1036.6 1737.8 ± 548.1 0.042 0.212 0.005 0.850AUC c‑pep Phase 3 1521.7 ± 490.0 2716.6 ± 1507.8 2832.4 ± 901.3 0.026 0.151 0.003 0.850ISR Baseline 1.3 ± 0.4 1.9 ± 0.9 1.9 ± 0.7 0.161 0.226 0.054 0.850ISR Phase 1 1.7 ± 0.8 3.4 ± 2.4 4.1 ± 2.1 0.008 0.076 0.002 0.345ISR Phase 2 2.8 ± 0.7 5.5 ± 3.5 5.4 ± 1.6 0.021 0.241 < 0.001 0.970ISR Phase 3 6.8 ± 2.6 13.1 ± 6.7 16.6 ± 6.9 0.006 0.064 0.001 0.241

Supported By: Fonds voor Wetenschappelijk Onderzoek-Vlaanderen

1903‑PBeta‑Cell Functional Capacity following Partial Pancreatectomy Is Predicted by Presurgery Impaired Beta‑Cell FunctionTERESA MEZZA, CHIARA M.A. CEFALO, GIAN PIO SORICE, FRANCESCA CINTI, SIMONA MOFFA, VINSIN A. SUN, FLAVIA IMPRONTA, SERGIO ALFIERI, ANDREA MARI, ANDREA GIACCARI, Rome, Italy, Padova, Italy

Several lines of evidence suggest that β-cell functional defects tem-porally anticipate (and eventually cause) the subsequent development of hyperglycemia, but the role of beta cell mass loss is still unclear. To fur-ther investigate the relative role of beta-cell mass reduction/dysfunction in the development of diabetes we performed oral glucose tolerance tests (OGTT) and hyperglycemic clamps (HC), followed by arginine stimulation, in 22 patients undergoing pancreatoduodenectomy (PD), pre- and post-surgery. Based on post-surgery OGTT, subjects were divided into 3 groups depend-ing on glucose tolerance: normal (NGT, n=6), impaired (IGT, n=6) or diabetic (DM, n=10) (12 F/10 M, 51±15 yrs.). To evaluate β-cell function, β-cell glucose sensitivity (GS) during HC was calculated as the ratio of insulin secretion and glucose increments. Before surgery, Arginine-stimulated Insulin Secre-tion rates (AIS) were similar across groups, whereas GS and incremental 1st phase insulin secretion were significantly lower in IGT and DM as compared with NGT subjects (p=0.02 and p<0.01). Following PD, AIS decreased in all patients (p<0.05 for all groups) but the reduction was greater in DM com-pared to IGT and NGT patients (p<0.001). A similarly scaled reduction was observed in 1st and 2nd phase of insulin secretion (p=0.03 and p<0.01) and in GS (p<0.01). Compared to baseline secretion, only DM group experienced a significant reduction in 2nd phase insulin secretion (348±118 vs. 105±40.3

A505


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



1908‑PPhysiological Determinants of Islet β‑ and α‑Cell Volume and Func‑tion in Nonhuman PrimatesRODOLFO GUARDADO-MENDOZA, PAUL B. HIGGINS, FRANCESCA CASIRAGHI, LILIA M. JIMENEZ-CEJA, EDWARD J. DICK, MA. DE LOURDES REYES-ESCOGIDO, ALBERTO M. DAVALLI, TERESA VANESSA FIORENTINO, FRANCO FOLLI, León, Mexico, San Antonio, TX, Milan, Italy, Catanzaro, Italy

Background: Maintenance of normal islet cell volume, function, and differ-ent cellular subtypes is crucial for the endocrine control of glucose homeo-stasis. We explored the interrelationships between β and α cell volume, β and α cell function, and body composition in healthy nonhuman primates.

Methods: Normoglycemic female baboons (Papio sp., n=28) underwent morphometry and body composition (DeXA) measurement, biochemical eval-uation, and 2-step hyperglycemic clamp (90mins/step) followed by L-arginine bolus (0.5g/kg) prior to partial pancreatectomy. α cell function was quanti-fied using the decremental area over the glucagon curve (0-90mins.) and the incremental area under the glucagon curve after arginine stimulus. β cell function was quantified using the disposition index (0-90mins). Islet cell vol-ume as well as β and α cell volumes were evaluated by immunocytochem-istry using the Computer Assisted Stereology Toolbox (CAST) 2.0 system (Visiopharm, Denmark).

Results: β cell volume and function were correlated (r=0.42, p=0.04). β cell volume was also correlated with body weight (r=0.65, p<0.01), abdominal circumference (r=0.53, p=0.01), and trunk fat mass (r=0.57, p<0.01). In con-trast, α cell volume and function were not correlated. α cell volume was cor-related with body weight (r=0.46, p=0.03), abdominal circumference (r=0.46, p=0.02), trunk fat mass (r=0.44, p=0.03), total body fat mass (r=0.45, p=0.02), and plasma total cholesterol (r=0.44, p=0.04). α cell function was correlated with fasting plasma glucagon (r=0.69, p<0.01), glucose (r=0.47, p<0.01) and insulin (r=0.63, p <0.01), and negatively correlated with age (r=-0.38, p=0.04).

Conclusion: β cell function is directly related to β cell volume in normal healthy baboons. Both β and α cell volume are related to body weight and composition and are strongly related to indices of central adiposity.

Supported By: National Institutes of Health (R01080148)

1909‑PNeuromedin U May Act as a Decretin Hormone by Attenuating the Glucose‑Lowering Effects of Glucagon‑Like Peptide‑1RUNE E. KUHRE, CHARLOTTE B. CHRISTIANSEN, MARIA N. GABE, RASMUS HYTTING-ANDREASEN, REIDAR ALBRECHTSEN, METTE M. ROSENKILDE, NICO-LAI J. WEWER ALBRECHTSEN, JENS J. HOLST, Copenhagen, Denmark

Studies on isolated islets of Langerhans have suggested that the peptide Neuromedin U (NMU) acts as a so-called decretin hormone, inhibiting glu-cose-stimulated insulin secretion. However, it is unknown whether a decre-tin effect of NMU can be demonstrated in a physiological setting. Using in vivo and isolated perfused pancreas studies in the rat (280-350g), we inves-tigated the effects of NMU on blood glucose and pancreatic hormone secre-tion and whether NMU counter-acts the glucose-lowering and insulin stimu-lating effects of glucagon-like peptide-1 (GLP-1). Intravenous administration of GLP-1 (GLP-1: 2nmol/kg body weight) + glucose decreased blood glucose excursions and peak-value compared to glucose alone (iAUC: glucose = 27.6±2.9 min x mM vs. glu.+GLP-1 = 20.9±3.2 min x mM, n=10), and this effect was attenuated by NMU(63 nmol/kg) (iAUC: glu.+GLP-1+NMU=24.1±2.2 min x mM, n=10). GLP-1 potentiated glucose-stimulated insulin secretion 3-fold (iAUC glu.=34.8±8.6 min x pg/ml vs. glu.+GLP-1=92.2±16.9 min x pg/ml, n=10, P <0.01), and this effect was unaffected by NMU administration (iAUC= 66.6±9.4 min x pg/ml, n = 10, P=0.22 compared to glu.+GLP-1 group). NMU did not change the secretion of glucagon, insulin or somatostatin from iso-lated perfused rat pancreas during glucose levels at 3.5 or 10 mM, and did also not affect GLP-1 stimulated insulin and SST secretion (n=6-7). In same experiments L-arginine robustly elevated the secretion of all peptides in all experiments, and the synthetic NMU used for the in vivo and perfusion stud-ies activated the NMUR1 in transient transfected COS-7 cells with a potency of 19nM (logEC50 -7.7±0.11, n=3). NMUR2, but not NMUR1, was detected in the rat pancreas but exclusively in the exocrine pancreas. We conclude that in the rat NMU counteracts the hypoglycemic effects of GLP-1 by pancreas-hormone-independent mechanisms and that antagonizing NMU’s effects with the purpose to lower blood glucose levels deserves further attention.

Supported By: Novo Nordisk Foundation; European Union’s Seventh Framework Programme for Research, Technological Development, and Demonstration Activi-ties (266408)

parameters should be considered when predicting the progression of predia-betes to T2DM in AAW with obesity.

Supported By: American Diabetes Association (1-11-CT-39 to K.O.)

1906‑PLow Pancreas Volume and High Intrapancreatic Fat Content Are Distinct Characteristics of Early Type 2 DiabetesAHMAD AL-MRABEH, SVIATLANA ZHYZHNEUSKAYA, CARL PETERS, ALISON BARNES, KIEREN HOLLINGSWORTH, HELEN PILKINGTON, MIKE LEAN, ROY TAY-LOR, Newcastle upon Tyne, United Kingdom, Glasgow, United Kingdom

Pancreas fat content has been shown to be raised in type 2 diabetes as quantified by a validated, precise magnetic resonance method. We have evaluated pancreas fat content in the baseline dataset of the prospec-tive, randomized Diabetes Remission Clinical Trial (DiRECT) of people with type 2 diabetes of less than 6 years duration. Detailed metabolic and mag-netic resonance studies were carried out on the Tyneside cohort (n=93; 52.8±7.9 years; weight 99.7±16.3 kg; BMI 34.5±4.3 kg/m2; diabetes duration 2.9±1.6 years). Comparative data from a nondiabetic control group (49.7±7.5 years; weight 101.5±10.2 kg; BMI 33.4±2.7 kg/m2) are shown. Pancreatic fat content was raised at 8.3±2.2% (nondiabetic 6.2±3.9%; p<0.02). The mean volume of the pancreas was low at 62.8± 16.3cm3 (normal 82.6±18.1cm3; p=0.004). VLDL1-triglyceride production rate was 547±178 mg/kg/day lead-ing to a total VLDL1-triglyceride pool size of 2372±1751 mg. Pancreas fat content correlated positively with BMI (r=0.28, p=0.007). There was no correlation between VLDL1-triglyceride pool size and pancreas fat (r=0.14, p>0.05). Pancreas volume correlated with fasting plasma insulin (r=0.32, p=0.001). Pancreas volume decreased with age (r=-0.25, p=0.02) but was not related to diabetes duration within the narrow range of diabetes duration in this cohort. High fat content of the pancreas and low pancreas volume are distinct characteristics of early type 2 diabetes. Further work is required to determine whether a small pancreas predisposes to type 2 diabetes or whether this is a consequence of the disease process. Additionally, pan-creas volume and fat content may be useful as prognostic markers for pro-gression to type 2 diabetes.

Supported By: Diabetes UK

1907‑PInsulin Sensitivity, Longevity Analysis, and Liver Proteomic and Transcriptomic Profiles Reveal Diet‑Independent Benefits of Life‑long Moderate Insulin ReductionJAMES D. JOHNSON, NICOLE M. TEMPLEMAN, STEPHANE FLIBOTTE, JENNY H.L. CHIK, SUNITA SINHA, GARETH E. LIM, LEONARD J. FOSTER, COREY NISLOW, Vancouver, BC, Canada

The causal relationships between insulin levels, insulin resistance, and longevity are unresolved. Genetic down-regulation of insulin/insulin-like growth factor 1 (Igf1) signaling components can extend invertebrate and mammalian lifespan, but insulin resistance, a natural form of decreased insulin signaling, is associated with greater risk of age-related disease in mammals. We compared Ins2+/- mice to Ins2+/+ littermate controls, on an Ins1-null background. Halving Ins2 resulted in a 25-34% reduction in circu-lating insulin in aged female mice, without altering Igf1 mRNA, circulating Igf1, Igf1 receptors, or Igf1 binding proteins. However, proteomic and tran-scriptomic analyses of livers from 25 week-old mice suggested potential for healthier aging and altered insulin sensitivity in Ins2+/- mice. Specifically, quantitative proteomic analysis revealed that mice with reduced insulin had significantly higher protein levels of Slco1b2, Dld, Cyb5b and Rpl23a. RNA sequencing identified further changes involved in proteostasis, cellu-lar metabolism/redox, and cholesterol synthesis. Remarkably, decreasing insulin led to lower fasting glucose via improved insulin sensitivity in aged mice, indicating that hyperinsulinemia itself contributes to age-dependent insulin resistance. Moreover, mice with lower insulin had lifespan exten-sion, observed across two diverse diets. The increased longevity was not associated with a dramatic protection from any specific disease, but rather a generalized improvement in healthspan. Our study indicates that elevated insulin contributes to age-dependent insulin resistance, and that limiting insulin can extend lifespan.

Supported By: Canadian Institutes of Health Research

A506


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


INTEGRATED PHYSIOLOGY—LIVER

& 1912‑PDefining a Novel Role of Distinct Membrane Trafficking Regulators in Blood Glucose HomeostasisSUSANNE SEITZ, SOFIYA GANCHEVA, SEBASTIAN KRAEMER, MARTIN HRABE DE ANGELIS, MICHAEL RODEN, STEPHAN HERZIG, ANJA ZEIGERER, Neuherberg, Germany, Düsseldorf, Germany

The increase in the prevalence of type 2 diabetes has reached an epidemic stage. The liver plays a central role in the development of type 2 diabetes due to its function in whole body glucose homeostasis. This is achieved by two cellular modules: glucose metabolism and endocytosis. Endocytosis is required for the uptake and signal transduction of growth factors, signal-ing receptors and hormones. The storage or release of glucose through a tight control of glucose metabolism allows maintaining whole body glucose homeostasis. These two modules need to be synchronized to control glucose metabolism, where dysfunctions in this process promote the development of type 2 diabetes. Recent evidences suggest that endocytosis participates in regulating glucose metabolism. First, overexpression of Rab25 in cells increased cellular glycogen stores to enhance survival during energetic stress. Second, depletion of the endosomal PI-3-kinase, Vps34 in mice led to hepatomegaly, hepatic steatosis and to a defect in glycogen storage. Third, knockdown of Rab5 in mouse liver caused hypoglycemia due to an inhibition of liver glucose production. Strikingly, loss of Rab5 in diabetic db/db mice res-cued their hyperglycaemia highlighting a potential therapeutic application. Here, we report a novel trafficking player in the control of liver metabolism, which functions as a rate-limiting component of the ESCRT (Endosomal Sort-ing Complexes Required for Transport)-3 complex involved in multi-vesicu-lar body/late endosome formation. We find this ESCRT-3 component to be upregulated in the liver of db/db mice and in patients with NAFLD and NASH. Intriguingly, ESCRT-3 participates in regulating glucose metabolism and mito-chondrial function in primary mouse hepatocytes in vitro and in mouse liver in vivo. Our data provide novel insights into the intracellular regulation of glucose metabolism and pave the way for their exploitation in the control of hepatic glucose production and thus the treatment of type 2 diabetes.

Supported By: German Research Foundation; German Center for Diabetes Research; European Foundation for the Study of Diabetes

& 1913‑PRenal Denervation Stimulates Hepatic Glucose Uptake in Chow‑Fed DogsGUILLAUME KRAFT, L. MERKLE MOORE, MELANIE SCOTT, ERIC ALLEN, DALE S. EDGERTON, HEATHER L. SARA, PHIL WILLIAMS, ALAN D. CHERRINGTON, Nashville, TN

Renal sympathetic denervation (RDN) has generated considerable interest as a way to treat drug-resistant hypertension. Recent data has confirmed that RDN can improve insulin sensitivity in different models of diet induced obesity. The objective of this study was to investigate the effect of renal denervation on liver glucose metabolism in normal dogs without insulin resistance. Dogs underwent either a surgical renal sympathetic denervation (RDN, n=5) or sham surgery (SHAM, n=6) and two weeks later we performed a 3 hour hyperinsu-linemic hyperglycemic pancreatic clamp. The arterial concentrations of insulin were 27±4 and 29±1 μU/mL, glucagon levels were 36±4 and 36±5 pg/mL and glucose levels were 210±4 and 213±4 mg/dL during the last 90 min of the clamp in SHAM and RDN respectively. Net hepatic glucose uptake was doubled in the RDN group relative to the SHAM group (1.9±0.3 vs. 4.2±0.7 mg/kg/min, respec-tively, P<0.01). NE content of both kidneys was decreased by an average of 93% indicating almost complete denervation. Liver NE content was also substan-tially decreased in the RDN group, but there was little impact of RDN on duode-nal or pancreatic NE (Table). These data suggest that renal denervation reduced an afferent signal from the kidneys to the brain, which in turn lowered the effer-ent tone to the liver, leading to an increase in net hepatic glucose uptake.

Table. Norepinephrine Content (ng/g of Tissue) in Organs of SHAM Operated and Renal Denervated Animals Collected at the End of the Study.

SHAM (n=6)

Renal Denervation (n=5)

% decrease

P value

Right Kidney 665±135 55±18 92 <0.001Left Kidney 694±97 39±20 94 <0.001Liver 267±42 59±30 78 0.003Duodenum 183±49 116±32 37 0.30Pancreas 534±48 392±93 27 0.18Values are the average of 2 biopsies of the renal cortex, 2 liver lobes, 1 biopsie of the duodenum and 3 biopsy of the pancreas.


1910‑PSerum Levels of Amylase Are Associated with the Progression of Metabolic Syndrome and the Development of Diabetes in Nonhu‑man PrimatesUDDHAV K. CHAUDHARI, JENNIFER D. NEWCOMB, BARBARA C. HANSEN, Tampa, FL

Low levels of serum amylase are associated with the development of metabolic syndrome (MetSyn) and diabetes (T2DM) in humans however, the mechanisms underlying the association between low amylase and the development of MetSyn remain poorly understood. In the present study, we evaluated the progression of MetSyn and its association with serum amylase levels in nonhuman primates (NHPs). A colony of rhesus monkeys (N=173, males=126; age 4 to 40 yrs; wt 4 to 27 kgs), continuously provided a healthy chow diet, was studied longitudinally and the progression of MetSyn characterized from metabolically normal to overt diabetes.

The metabolically normal group of monkeys had the following character-istics: mean (± SD) age 9.9 ± 2.2 yrs, wt 11.6 ± 2.3 kg, fasting insulin (FIns) 61.8 ± 12.2 μU/ml, acute insulin response to IV glucose (AIR) 189.1 ± 14.7 μU/ml/min, glucose disappearance rate (Kgluc) 3.8 ± 0.2 μU/ml/min, fasting plasma glucose (FPG) 63.9 ± 1.9 mg/dl, TG 61.8 ± 8.4 mg/dl, insulin sensitivity by euglycemic clamp (IS)11.3 ± 1.7 mg/kg FFM/min and amylase 236.0 ± 11.8 U/L. NHPs with MetSyn had a mean age of 16.5 ± 1.2 yrs, wt 16.9 ± 0.5 kg, FIns 214 ± 65.5 μU/ml, AIR 298.5 ± 89.3 μU/ml/min, Kgluc 2.5 ± 0.2 μU/ml/min, IS 5.2 ± 0.6 mg/kg FFM/min, TG 237.5 ± 27.7 mg/dl with a significantly lower serum amylase level of 193.4 ± 7.3 U/L compared to normal monkeys (p <0.001). NHPs with T2DM were characterized by a decrease in IS with increased FPG 176.1 ± 2.9 mg/dl, HbA1c% 8.1, and TG 487.9 ± 29.4 mg/dl and lower amylase 184.5 ± 4.8 U/L levels. Insulin-treated NHPs, showed a further decrease in amylase 167.5 ± 5.4 U/L. Decreased levels of serum amy-lase are associated with the progression of MetSyn, insulin resistance and development of T2DM in NHPs. This association of decreasing amylase with declining glucose tolerance has also been reported in humans (Nakajima, 2011). NHPs provide an ideal model for the study of underlying mechanisms of this disease progression.



Moderated Poster Discussion: Integrated Physiology—Liver (Posters: 1911-P to 1916-P), see page 19.

1911‑P

WITHDRAWN

A507


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



& 1916‑PANGPTL8 Antisense Oligonucleotide Promotes Lipid Update in White Adipose and Prevents Hepatic Steatosis and Insulin Resis‑tance in High‑Fat‑Fed RodentsDANIEL F. VATNER, LEIGH GOEDEKE, ALI R. NASIRI, SANJAY BHANOT, GLENN S. GERHARD, SUSAN F. MURRAY, CHRISTOPHER D. STILL, GERALD I. SHULMAN, VARMAN T. SAMUEL, New Haven, CT, Carlsbad, CA, Danville, PA

Angiopoietin-Like 8 (ANGPTL8) is an insulin-regulated protein thought to play an important role as an endogenous lipoprotein lipase inhibitor in white adipose tissue (WAT). We found that in severely insulin resistant obese indi-viduals WAT ANGPTL8 gene expression was increased by 7.6 fold (P<0.05) relative to matched obese insulin sensitive individuals. However, ANGPTL8 knockout mice demonstrate reduced plasma triglycerides but an other-wise unremarkable metabolic phenotype. To determine whether there is a potential causal role for ANGPLT8 in the progression of insulin resistance through alteration of lipid deposition, we examined whether knockdown of ANGPTL8 with a second generation antisense oligonucleotide (ASO) would prevent high fat feeding (HFF) induced ectopic tissue lipid deposition in liver and insulin resistance. HFF male C57BL/6 mice and SD rats were treated with an ANGPTL8 ASO (AN8) or a control ASO (CON) for 3 weeks (50 mg/kg-week). In HFF mice, AN8 increased whole body fat mass by 84% (P<0.01) and decreased hepatic triglyceride content by ~40% (P<0.0001) indepen-dent of changes in net whole body energy balance or body weight. In HFF rats, AN8 reduced plasma triglycerides by 50% (CON: 128±15 mg/dL; AN8: 52±5; P<0.001) and HOMA-IR by 58% (CON: 14±2; AN8: 6.0±1.0; P<0.001). This improvement in insulin sensitivity was associated with a 65% reduc-tion in hepatic steatosis in HFF rats (CON: 49±5 mg TG/g liver; AN8: 17±2; P<0.0001). During mixed meal tolerance tests in rats, hepatic chylomicron remnant clearance assessed by retinyl palmitate uptake was unchanged, but adipose uptake of meal-lipid as assessed by triolein uptake was increased by 43% (P<0.01) in epidydimal WAT and by 38% (P<0.01) in subcutaneous WAT.

Conclusion: ANGPTL8 is a key inhibitor of post-prandial WAT lipid uptake and knockdown of WAT ANGPTL8 expression improves adipose lipid uptake, preventing diet-induced hepatic steatosis and insulin resistance.

Supported By: National Institutes of Health (K23DK102874-01A1)

1917‑PExendin‑4 Suppresses Cholesterol Accumulation via Elevation of ATP‑Binding Cassette Transporter A1 in the LiverJINGYA LYU, HITOMI IMACHI, KENSAKU FUKUNAGA, XIAOZHOU ZHANG, TAO DONG, SEISUKE SATO, TOMOHIRO IBATA, NAO YAMAJI, KAZUKO YONEZAKI, FUMI KIKUCHI, TAKUO YOSHIMOTO, KOJI MURAO, Kagawa, Japan

Exendin-4, a long-acting agonist of the glucagon-like peptide-1 (GLP-1) receptor, has been used as a therapeutic agent for diabetes and improves hepatic steatosis. ATP-binding cassette transporter A1 (ABCA1), which is identified as a mutated molecular in Tangier Disease, is a pivotal regulator of lipid efflux in reverse cholesterol transport (RCT). Specific deletion of ABCA1 in liver results in cholesterol accumulation and interrupting the RCT. In this study, we checked the effects of exendin-4 on ABCA1 expression in hepa-tocytes and investigated the detailed mechanism. Firstly, we demonstrated that exendin-4, binding to GLP-1 receptor, elevated ABCA1 expression and transcription in hepatocytes via CaMKK/CaMKIV pathway. As a result, exendin-4 decreased cholesterol content in HepG2. To understand the detailed mechanism, we employed chromatin immunoprecipitation (ChIP) assay to prove that Prolactin Regulatory Element Binding (PREB) mediates ABCA1 transcriptional activity and this effect was up-regulated by exen-din-4. Moreover, when PREB-site in ABCA1 promoter region was mutated, all the effects on ABCA1 transcription induced by exendin-4, inhibition of CaMKK, overexpression of CaMKIV or PREB did not persist. Further, silence of PREB attenuated the effects of exendin-4 on ABCA1 expression while silence of CaMKIV canceled the effects of exendin-4 on both ABCA1 and PREB, pointing out that exendin-4 regulates ABCA1 expression via CaMKIV/PREB. It was confirmed by in vivo experiments and treatment with exendin-4 (1 nmol/kg/day, 4 weeks) decreased the cholesterol accumulation in the liver of mice with high-fat diet.

In summary, our data demonstrated that exendin-4 facilitates cholesterol efflux in hepatocytes via elevation of ABCA1 mediated by CaMKK/CaMKIV/PREB, suggesting that exendin-4 used for diabetes has a potential function in suppressing cholesterol accumulation in liver.

& 1914‑PGap Junction Communication and Tissue Propagation of ER Stress in ObesityAMIR TIROSH, GUROL TUNCMAN, EDIZ CALAY, YANKUN G. LEE, ANA PAULA ARRUDA, ABDULLAH YALCIN, GÖKHAN S. HOTAMISLIGIL, Boston, MA

Endoplasmic reticulum stress (ERS) is an important mechanism in the pathophysiology of obesity induced insulin resistance. While the cellular events linking ERS and insulin resistance are well characterized, the role of cell-cell communication and the coordinated response at the tissue level is unclear. Increased gap junction (GJ)-intercellular communication, primarily composed of connexin (Cx)43, was shown to play a key role in the maladap-tive tissue response to various stresses, and was implicated in the patho-genesis of atherosclerosis and neurodegenerative diseases, which similarly to obesity, are characterized by chronic low-grade inflammation and ERS. In this study we demonstrate that ERS resulted in increased gene and pro-tein expression of Cx43 in various cell lines, and in increased GJ mediated cell-cell coupling. Co-culture of ER stressed cells with ERS-naïve (recipient) cells resulted in inter-cellular transmission of ERS signals and activation of the unfolded protein response in intact cells (‘bystander response’). This response resulted in chaperon consumption and impaired folding capacity of the recipient cells. The propagation of ERS required cell-cell contact, and Cx43 knock down prevented the transmission of ERS from ‘stressed’ cells to ERS naïve cells. Diet induced obesity in mice resulted in hepatic ERS and accordingly, in upregulation of Cx43 in the liver. In addition, co-culture of iso-lated hepatocytes from HFD mice with hepatocytes from lean mice resulted in transmission of ERS from obese hepatocytes to the intact hepatocytes in a Cx43-dependent manner. Mice lacking Cx43 specifically in the liver were protected from HFD-induced liver ERS, insulin resistance and hepatosteato-sis. Taken together, our results suggest that in obesity, the increased Cx43-mediated cell-cell coupling may become maladaptive by allowing tissue propagation of ERS. This maladaptive response to over-nutrition may further aggravate liver ERS and worsen hepatic and systemic insulin resistance.

Supported By: National Institute of Diabetes and Digestive and Kidney Diseases (K08 DK097145 to A.T.)

& 1915‑PMIP1α Deficiency Prevents Lipotoxicity‑Induced Hepatic Insulin Resistance and SteatohepatitisLIANG XU, MAYUMI NAGASHIMADA, GUANLIANG CHEN, TSUGUHITO OTA, Kanazawa, Japan

We reported previously that loss of the C-C chemokine receptor CCR5 prevents obesity-related insulin resistance independently of MCP-1-CCR2. Moreover, we found that hepatic expression of macrophage inflammatory protein 1α (MIP1α), a CCR5 ligand, increases markedly in obese mice. To investigate the role of MIP1α in lipotoxicity-induced hepatic insulin resis-tance and nonalcoholic steatohepatitis (NASH), the metabolic phenotypes of MIP1α-/- mice and their littermates were compared by feeding them a high-cholesterol/high-fat (CL) diet for 16 weeks. Expression of MIP1α mRNA increased significantly in the liver of wild type (WT) mice fed the CL diet compared with that in chow fed WT mice (P < 0.01), particularly in the macrophage/Kupffer cell fraction. An immunofluorescence analysis of the liver revealed that MIP1α was expressed by F4/80+ macrophages in CL fed mice. The excess hepatic lipid accumulation and peroxidation induced by the CL diet decreased in MIP1α-/- mice compared with those in MIP1α+/+ mice (P < 0.01). CL diet-induced glucose intolerance and hyperinsulinemia improved in MIP1α-/- mice compared with those in MIP1α+/+ mice. In addition, phosphorylation of IRβ and Akt was enhanced in the liver of MIP1α-/- mice, accompanied by attenuated NF-κB and MAPK signaling, and decreased plasma TNFα levels (P < 0.05). Furthermore, CL diet-induced stellate cells activation and fibrogenesis decreased in the liver of MIP1α-/- mice. A flow cytometry analysis demonstrated that MIP1α-/- mice fed the CL diet had 37% fewer CD11c+CD206-(M1) macrophages but 59% more CD11c-CD206+

(M2) macrophages than those in MIP1α+/+ mice, resulting in a predominance of M2 over the M1 population. Importantly, chimeric mice lacking MIP1α only in myeloid cells (MIP1α-/- into MIP1α+/+ bone marrow transplant) were protected from CL diet-induced insulin resistance and NASH. Thus, MIP1α deficiency prevented lipotoxicity-induced insulin resistance and NASH by polarizing M2 macrophages in the liver.

Supported By: Japan Ministry of Education, Culture, Sports, Science and Technology

A508


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



1920‑PHepatic Hypoxia‑Inducible Factor 1alpha (HIF‑1alpha) Activation Promotes Cholesterol Gallstone FormationYOICHIRO ASAI, TETSUYA YAMADA, HIDEKI KATAGIRI, Miyagi, Japan

Hypoxia-inducible factor-1alpha (HIF-1alpha) is a key transcription factor for adaptation to hypoxia and is activated in nonalcoholic fatty liver disease (NAFLD). NAFLD is epidemiologically recognized as a risk factor for choles-terol gallstone disease, but the mechanistic links remain unknown. Herein, we show that hepatic HIF-1alpha activation promotes cholesterol gallstone formation. A cholesterol and cholate-rich diet induced liver steatosis with hypoxia and HIF-1alpha upregulation in hepatocytes around central veins and promoted cholesterol gallstone formation with marked gallbladder wall inflammation. Inducible hepatocyte-selective HIF-1alpha knockout mice were highly resistant to cholesterol gallstone formation with remarkably sup-pressed gallbladder wall inflammation. HIF-1alpha knockout in hepatocytes significantly upregulated expression of aquaporin-8 (AQP8), a water channel responsible for water secretion from hepatocytes into the bile canalicular lumen. Consistent with up-regulated AQP8 expression, hepatic HIF-1alpha deficiency increased bile flow with enhanced water secretion from hepato-cytes. This dilution of bile resulted in the decreased biliary lipids, prevent-ing cholesterol gallstone formation in KO mice. Furthermore, in cultured hepatocytes, hypoxic conditions downregulated AQP8 expression in a HIF-1alpha-dependent manner. Notably, in human NAFLD patients with gall-stones, hepatic expressions of HIF-1alpha and its down-stream targets were increased compared to those without gallstones. These findings indicate that HIF-1alpha upregulation by hypoxia in the steatotic liver condenses biliary lipids due to suppression of water secretion from hepatocytes, thereby pro-moting cholesterol gallstone formation. This mechanism, which likely holds true in human NAFLD subjects, is a potential therapeutic target for gallstone disease.

1921‑PA Common Set of Hepatic Long Noncoding RNAs (LNCRNAs) Define Inflammation and Severe Fibrosis in Nonalcoholic SteatohepatitisJOHANNA DISTEFANO, FATJON LETI, CHRISTOPHE LEGENDRE, CHRISTOPHER STILL, GLENN GERHARD, Denver, CO, Phoenix, AZ, Danville, PA, Philadelphia, PA

Nonalcoholic fatty liver disease (NAFLD) is considered the hepatic mani-festation of the metabolic syndrome. Recent studies have shown a role for long noncoding RNAs (LNCRNAs) in the development of NAFLD, but the contribution of these molecules to the development of nonalcoholic steato-hepatitis (NASH), a more clinically severe manifestation of NAFLD, remains poorly understood. We profiled LNCRNA expression using RNA-sequencing of wedge liver biopsies from NAFLD patients with liver histology showing either lobular inflammation or advanced fibrosis. Using a base mean ≥10 FPKM, log2 fold-change ≥ 1.0, and a false-discovery rate p-value ≤ 0.05, we identified 123 LNCRNAs shared between profiles from lobular inflammation and fibrosis. We selected eight of these LNCRNAs for validation using quan-titative polymerase chain reaction. Among these LNCRNAs, expression of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) was one of the most significantly increased transcripts in fibrotic tissue. We deter-mined that MALAT1 expression is regulated by hyperglycemia and insulin in liver cells in, and MALAT1 knockdown corresponded with downregulation of a predicted target gene, C-X-C motif chemokine ligand 5 (CXCL5). In fibrotic liver, CXCL5 expression was significantly upregulated at both transcript and protein levels compared to normal liver. We conclude that dysregulated LNCRNA expression is associated with inflammation and fibrosis in NASH, and functionally relevant differences in MALAT1 expression may contribute to the development of fibrosis in the disease through mechanisms involving inflammatory chemokines.


1922‑PRole of the Gut in Glucose‑Induced Suppression of Bone Resorp‑tion in Patients with Nonalcoholic Fatty Liver Disease and/or Type 2 DiabetesHENRIK MAAGENSEN, ANDERS E. JUNKER, NIKLAS R. JØRGENSEN, LISE L. GLUUD, FILIP K. KNOP, TINA VILSBØLL, Hellerup, Denmark, Glostrup, Denmark, Hvidovre, Denmark

Nonalcoholic fatty liver disease (NAFLD) is associated with decreased bone mineral density (BMD), while type 2 diabetes (T2D) is associated with normal to high BMD. Both conditions are associated with increased fracture risk. The pathophysiology underlying bone abnormalities in NAFLD and T2D remain uncertain, but may involve the gut-bone axis. We investigated the influence of the gut on postprandial bone resorption in healthy individuals

1918‑PEvaluation of the Association of Single Nucleotide Polymorphisms in the Sodium‑Glucose Cotransporter 2 Gene with Glucose Homeo‑stasis and Type 2 DiabetesAXEL MUENDLEIN, JANINE EBNER, ANDREAS LEIHERER, CHRISTOPH H. SAELY, KATHRIN GEIGER, EVA M. BRANDTNER, DANIELA ZANOLIN, ALEXANDER VON-BANK, PETER FRAUNBERGER, HEINZ DREXEL, Dornbirn, Austria, Triesen, Liechten-stein, Feldkirch, Austria, Philadelphia, PA

Sodium glucose cotransporter 2 (SGLT2) is the major transporter involved in glucose reabsorption in the kidney and mutations in the SGLT2 encod-ing gene SLC5A2 cause renal glucosuria. However, the association between genetic variation in SLC5A2 and T2DM is still unclear and is addressed in the present study. We genotyped the SLC5A2 tagging SNPs rs9934336, rs3813008, and rs3116150 (completely capturing all common genetic varia-tions in the gene locus of SLC5A2 according to HapMap SNP database, release 27) in 1,684 coronary patients, including 400 patients with T2DM. The rare allele of rs9934336 was significantly associated with decreased fasting glucose and 2-hour glucose in oral glucose tolerance tests (p=0.041 and 0.035, respectively) as well as decreased HbA1c and estimated aver-age fasting glucose (p=0.033 and 0.026, respectively). Further, variant rs9934336 was significantly associated with the presence of T2DM, in univariate (OR=0.82 [0.68-0.99]; p=0.037) as well in multivariate regres-sion analysis adjusting for age, sex, body mass index, metabolic syndrome, hypertension, and estimated glomerular filtration rate (OR=0.79 [0.64-0.95]; p=0.019). However, rs9934336 was not associated with serum insulin, or with the homeostatic model assessment indices of insulin resistance and beta cell function, respectively. Polymorphisms rs3813008 and rs3116150 were neither associated with fasting or postchallenge glucose nor with T2DM. We conclude that genetic variation within the SLC5A2 gene locus contributes to fasting as well as postchallenge plasma glucose and to the manifestation of T2DM.

1919‑PThe Metabolic Roles of Heat Shock Protein 72 in Mice Model of DiabetesTATSUYA KONDO, SAYAKA KITANO, RIEKO GOTO, KAORU ONO, MOTOYUKI IGATA, JUNJI KAWASHIMA, HIROYUKI MOTOSHIMA, TAKESHI MATSUMURA, HIROFUMI KAI, EIICHI ARAKI, Kumamoto, Japan

Cell stresses, such as endoplasmic reticulum stress or oxidative stress is one of the key mediators in pathophysiology of type 2 diabetes. Molecu-lar chaperone, which modulate protein folding and/or assembly and protect cells from those stresses, may be a favorable target for diabetic treatment. Heat shock protein (HSP) 72 is a major inducible heat shock protein against heat, ultraviolet, heavy metals or infection, and serves to protect cells from those cellular stress signals. Induction of HSP72 by pharmacologic agent or mild electrical stimulation with heat shock improves glucose intolerance in diabetic model mice. In this study, we investigated glucose metabolism in whole body HSP72 deficient (KO) mice to explore the roles of HSP72 in dia-betes. Male HSP72 KO mice or control (C) mice were subjected to a high-fat diet (HFD) regimen for 16 weeks. KO mice showed significantly higher body weight after 10 weeks of HFD (KO: 36.9g vs. C: 33.4g). Fasting blood glucose was significantly elevated after 11 weeks of HFD (KO: 143.3mg/dL vs. C: 115.5mg/dL). Random fed blood glucose and food intake were comparable. Upon glucose challenge test, blood glucose levels at any time points mea-sured were higher in KO mice. On insulin tolerance test, KO mice exhibited insulin resistant phenotype. Visceral fat mass was increased and hepatic steatosis was obvious in KO mice. Upon insulin stimulation, phosphoryla-tion of Akt was decreased by approximately 50% in KO liver, with increased activation of c-jun N-terminal kinase. Hepatic gluconeogenesis was not suppressed in KO mice. When adding back to HSP72 expression in liver by lenti-viral system on HFD fed KO mice, fasting blood glucose was reversed compared to C mice on HFD.

In summary, deficiency of HSP72 leads to increased visceral adiposity, hepatic insulin resistance, glucose intolerance and fatty liver. As induction of HSP72 is beneficial to treat diabetes, our observations strongly indicate the abundance of HSP72 is critical in diabetic pathophysiology.


A509


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



of human SEPP1 and HIP/PAP upstream of a luciferase reporter gene and transfected them into HepG2 cells. The promoter activities of SEPP1 and HIP/PAP were not increased by IH. Target mRNA search of microRNA (miR)s using MicroRNA.org program revealed that both mRNAs have a potential target sequence for miR-203. The levels of miR-203 and mRNAs involved in biosynthesis and degradation of miRs (TP63, DROSHA, DICER, and MCPIP1) were measured by real-time RT-PCR. The miR-203 level of IH-treated cells was significantly decreased than that of normoxia-treated cells (P=0.0391). To clarify the role of miR-203, miR-203 inhibitor and non-specific control RNA (miR-203 inhibitor NC) were introduced into HepG2 cells and the mRNA levels of SEPP1 and HIP/PAP were measured. The IH-induced expression of SEPP1 and HIP/PAP was abolished by introduction of miR-203 inhibitor but not by miR-203 inhibitor NC. We concluded that IH stress down-regulates the miR-203 in hepatocytes, resulting in the increased levels of SEPP1 and HIP/PAP mRNA via the inhibition of the miR-203-mediated mRNA degrada-tion, leading SAS patients to insulin resistance.

1925‑PDeficiency of IL‑17A Alleviates High‑Fat Diet plus LPS‑Induced Liver Injury In MiceWEI XIANG, XIAODONG WANG, LIXIA GAN, Chongqing, China

Increased serum LPS and IL-17A has been linked to obesity and are associ-ated with progression of NAFLD. This study characterized the role of IL-17A using a NAFLD mouse model. Mice were fed HF diet for 3 months and then given LPS (4mg/kg) via ip injection. We have shown that deficiency of IL-17A significantly ameliorated liver injury reflected by decreased serum ALT and AST levels. Reduced neutrophile and monocytes were also seen in KO liver under this condition, with lower levels of TNF-α, IL-1βand IL-6. Transcrip-tomics analysis of liver tissues revealed that IL-17A KO significantly decreased a panel of chemoattractant factors for neutrophil and monocytes, such as CCL2, CCL7, CCL8, CXCL1, CXCL10 and CXCL14. Further, proteomics showed a markedly decrease in macrophage activation featured by decreased expres-sion of macrophage inflammatory protein (MIP)-2 and chitotriosidase in KO mice. Specifically, a panel of metabolic enzymes participating in H2O2 detoxi-fication, such as GPX1, IDH1 and ME1 were significantly higher shown by pro-teomics in KO mice. In support, ROS levels in KO mice liver were significantly decreased as shown by lowered MDA and increased catalase, NADPH and T-AOC compared to WT mice. Tunnel staining showed a markedly reduced apoptotic cells in KO liver. Taken together, these results suggest that IL-17A acts to promote LPS-induced steatotic liver injury. Blocking IL-17A may pro-tect NAFLD progression under constant LPS challenge in obese humans.

Supported By: National Natural Science Foundation of China

1926‑PWeight Loss‑Induced Changes in Intrahepatic Fat and Insulin Sen‑sitivity in Individuals with Impaired Fasting Glucose: A PREVIEW StudyMATHIJS DRUMMEN, ANNE RABEN, MIKAEL FOGELHOLM, MARGRIET WESTERTERP-PLANTENGA, TANJA ADAM, Maastricht, Netherlands, Copenhagen, Denmark, Helsinki, Finland

Nonalcoholic fatty liver disease (NAFLD) is one of the leading causes of chronic liver disease, and poses a 2 to 5-fold risk to develop type 2 diabetes (T2D), corroborating the role of intrahepatic fat for insulin resistance and as a target for the prevention of T2D. The aim of the study was to assess the effect of an 8-week weight loss period and subsequent 18-weeks weight maintenance on changes in intrahepatic lipid content (IHTG) and the impli-cations for insulin sensitivity in individuals with impaired fasting glucose. Participants are part of PREVIEW, a study to determine effective lifestyle factors for T2D prevention.

In 24 obese individuals (m/f: 12/12; BMI: 31.4±3.7 kg/m2; fasting glucose: 6.4±0.6 mmol/l; fasting insulin: 12.9±4.9 mU/l) IHTG content and glucose tol-erance (GT) were determined by proton magnetic resonance spectroscopy and oral glucose challenge. All outcome parameters including anthropomet-rics and inflammatory parameters were assessed before and after weight loss and weight maintenance.

After 26 weeks, weight loss was 10.6±4.1%. IHTG content was reduced from 8.7±8.5% to 2.3±2.7% (p<0.01), and HOMA-IR from 3.6±1.4 to 2.3±0.87 (p<0.01). BMI, body fat percentage, and HbA1c decreased significantly over time (all p<0.01). Changes in IHTG were positively associated with changes in HOMA-IR (r=0.56; p<0.01), BMI (r=0.62; p<0.01), systolic blood pressure (r=0.52; p<0.05), and HbA1c (r=0.44; p<0.05). In a subsequent regression analysis considering changes in liver fat, BMI, body fat percentage and age, liver fat stayed the only significant predictor for changes in HOMA-IR in all four models (p<0.01).

and patients with T2D and/or biopsy-verified NAFLD. NAFLD patients with normal glucose tolerance [n=8, HbA1c: 33 (32, 37) mmol/mol (median with IQR in brackets); BMI: 30 (26, 35) kg/m2], NAFLD patients with T2D [n=8, HbA1c: 50 (41, 53) mmol/mol; BMI: 30 (28, 32) kg/m2], T2D patients without liver disease [n=8, HbA1c: 43 (39, 48) mmol/mol; BMI: 28 (26, 28) kg/m2] and healthy controls [n=9, HbA1c: 36 (34, 37) mmol/mol; BMI: 28 (28, 29) kg/m2] underwent a 4-hour 50g oral glucose tolerance test (OGTT) and an isoglyce-mic intravenous glucose infusion (IIGI) with repeated measurements of the bone resorption marker C-terminal type I collagen telopeptide (CTX). Plasma glucose levels achieved during OGTTs were successfully matched on corre-sponding IIGI days. Patients with NAFLD+T2D exhibited similar CTX suppres-sion (as assessed by AUC0-4 h for percent change from baseline) on OGTT vs. IIGI [-94 (-117, -70) vs. -114 (-129, -68)%×h, P=0.46], while remaining groups showed greater (P<0.05) CTX suppression during OGTT vs. IIGI (healthy sub-jects [-111 (-136, -93) vs. -66 (-102, -30)%×h], NAFLD [-145 (-162, -124) vs. -97 (-108, -44)%×h], and T2D [-79 (-96, -49) vs. -20 (-37, 32)%×h]).

In conclusion, OGTT-induced potentiation of CTX suppression seems to be abolished in patients with NAFLD+T2D, but preserved in patients with either NALFD or T2D. This suggests that coexistence of T2D and NAFLD may disturb the gut-bone axis.

1923‑PDisruption of A2AR Exacerbates Aspects of Diet‑Induced NAFLD and Increases Hepatic SREBP1c Expression under Fasted StatesYULI CAI, HONGGUI LI, MENGYANG LIU, YA PEI, SHIH LUNG WOO, YUQING HUO, CHAODONG WU, College Station, TX, Augusta, GA

Nonalcoholic fatty liver disease (NAFLD) is characterized by hepatic fat deposition (steatosis) and inflammation. These two aspects of NAFLD also interplay with insulin resistance to cause or exacerbate hyperglycemia and hyperlipidemia of type 2 diabetes. Much evidence has demonstrated an anti-inflammatory effect of adenosine 2A receptor (A2AR). However, the exact role for A2AR in NAFLD remains poorly understood. In the present study, A2AR-deficient mice and wild type (WT) C57BL/6J mice were fed a high-fat diet (HFD) for 12 weeks to examine the involvement of A2AR in NAFLD. Additional mice were free-fed or fasted overnight for tissue harvest and/or isolation of primary hepatocytes for the assays to gain insights of A2AR regulation of fat deposition and events related to lipogenesis. Compared with HFD-fed WT mice, HFD-fed A2AR-deficient mice displayed a significant increase in the severity of hepatic steatosis and inflammation, which was accompanied with increased severity of systemic insulin resistance and dys-regulation of glucose homeostasis. Consistent with increased hepatic ste-atosis, the expression of liver genes for lipogenesis was increased in HFD-fed A2AR-deficient mice compared with HFD-fed WT mice. While exploring transcriptional control of lipogenesis, the present study also revealed that hepatic amount of cytosolic sterol regulatory element-binding protein 1c (SREBP1c) in A2AR-deficient mice was significantly higher than that in WT mice under fasted conditions, but not fed conditions. In addition, the amount of cytosolic SREBP1c in hepatocytes isolated from A2AR-deficient mice was significantly higher than that in WT hepatocytes upon nutrient starvation. Taken together, these results suggest that A2AR plays a critical role in pro-tecting against diet-induced aspects of NAFLD. Mechanistically, A2AR likely decreases hepatic lipogenesis through suppressing SREBP1c expression under fasted conditions.

Supported By: American Diabetes Association (1-13-BS-214-BR to C.W.); DK095862

1924‑PUpregulation of Selenoprotein P and HIP/PAP in Human Hepato‑cytes by Intermittent Hypoxia and Its mRNA‑Mediated MechanismTOMOKO UCHIYAMA, HIROYO OTA, ASAKO ITAYA-HIRONAKA, RYOGO SHO-BATAKE, AKIYO YAMAUCHI, SUMIYO SAKURAMOTO-TSUCHIDA, MAI MAKINO, HIROSHI KIMURA, MAIKO TAKEDA, CHIHO OHBAYASHI, SHIN TAKASAWA, Kashihara, Japan

Sleep apnea syndrome (SAS) is a risk factor for insulin resistance/type 2 diabetes. SAS is characterized by recurrent episodes of oxygen desatura-tion and reoxygenation (intermittent hypoxia (IH)). In the present study, we researched the mRNA levels of several hepatokines and REG (Regenerat-ing gene) family genes, coding growth factor for regeneration and prolif-eration. In experimental ‘IH’ or ‘normoxia’ condition, human hepatocytes (JHH5, JHH7, and HepG2) were exposed either to IH (5 min (5% CO2 · 1% O2)/10 min (5% CO2 · 21% O2)) or normoxia for 24 h. We found that the mRNA levels of selenoprotein P (SEPP1) and hepatocarcinoma-intestine-pancreas/pancreatitis-associated protein (HIP/PAP) were significantly increased by IH. We next prepared reporter plasmids by inserting the promoter fragments

A510


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



Short-term SGLT2I therapy improved liver histology in NAFLD patients with-out any relation to the extent of improvement of glucose tolerance.

1929‑PLY2405319, an Analog of FGF‑21 Ameliorates Liver Fibrosis through Succinate‑GPR91 Pathway in MiceEUN HEE CHO, JI YUN JEONG, JUNGUK HUR, Chuncheon, Republic of Korea, Gumi, Republic of Korea, Grand Forks, ND

Fibroblast growth factor-21 (FGF-21) is an important metabolic regulator and is expressed predominantly in the liver. In this study, we evaluate the role of LY2405319, an analogue of FGF-21 in hepatic stellate cells (HSCs) activation and methionine and choline-deficient (MCD)-diet induced mouse model of liver fibrosis. Liver fibrosis is the excessive accumulation of extra-cellular matrix (ECM) proteins and HSCs are the main ECM-producing cells in the injured liver. During liver injury, HSCs trans-differentiate into activated myofibroblasts which produce alpha-smooth muscle actin (α-SMA) and become a major cell type in hepatic fibrogenesis. Succinate and succinate receptor (GPR91) signaling has now emerged as a regulator to promote the expression of α-SMA in MCD diet-induced mice. Palmitate or MCD medium treatment increased succinate concentration of LX-2 cells (HSCs) and enlarged production of GPR91 and α-SMA. However, LY2405319 adminis-tration ameliorates palmitate or MCD media-induced escalated succinate production and over-expression of GPR91 and α-SMA in LX2-cells. LX-2 cells exposed to palmitate 300uM and MCD medium for 24 h caused the increased secretion of succinate concentrations in the whole conditioned medium and cell lysate. On the other hand, treatment of LY2405319 100nM alleviated significantly palmitate- or MCD medium-induced elevation of suc-cinate concentrations in the medium and cell lysate of LX 2 cells. In vivo study, the MCD diet treatment showed increased steatohepatitis and liver fibrosis compared with the control diet in mice. LY2405319 administration improved steatohepatitis and ameliorated GPR91 and α-SMA overexpres-sion in the liver of MCD diet-induced mouse model. These results show that FGF-21 reduces α-SMA production by inhibiting succinate-GPR91 pathway. FGF-21 acts as an inhibitor of the succinate-GPR91 pathway to control liver fibrosis. FGF-21 has the therapeutic potential for treating liver fibrogenesis.

Figures.

1930‑PHepatic SIRT1 Deficiency Abolishes Berberine‑Mediated Augmen‑tation of Autophagy and Reduction of Hepatic Steatosis in Diet‑Induced Obesity MiceYIXUAN SUN, YAMEI HAN, FEIFEI ZHANG, ZHIMIN HU, AOYUAN CUI, FENG-GUANG MA, ZHENGSHUAI LIU, QI GONG, XUQING CHEN, JING GAO, YI TAN, XIN GAO, YU LI, Shanghai, China, Louisville, KY

Berberine, a compound from rhizome coptidis, has drawn increasing attention for its therapeutic potential for treating hepatic steatosis, dys-lipidemia and diabetes. The underlying mechanism of berberine on lipid

Weight loss induced changes in liver fat appeared to be the most important predictor for the improvement in insulin resistance in individuals with impaired fasting glucose, independent of changes in BMI and general body fat.

Supported By: European Union Seventh Framework Programme (312057)

1927‑PContribution of Hepatic and Visceral Fat to Fasting Triglyceride‑Rich Lipoprotein Subclasses: The Federal Women StudySTEPHANIE T. CHUNG, MIRELLA GALVAN DE-LA CRUZ, ANTHONY ONU-ZURUIKE, AMBER B. COURVILLE, BRIANNA BINGHAM, RAFEAL BAKER, JEAN UTUMATWISHIMA, MADIA RICKS, LILIAN MABUNDO, MAUREEN SAMP-SON, RONALD OUWERKERK, ALAN REMALEY, AHMED M. GHARIB, ANNE E. SUMNER, Bethesda, MD

Obesity and visceral fat accumulation are associated with hypertriglyc-eridemia and increased risk for cardiometabolic disease. However, women of African descent have high rates of obesity and cardiometabolic disease but normal triglyceride (TG) concentrations. This TG paradox is only par-tially explained by low visceral fat content, but may be further clarified by delineating the association of triglyceride rich lipoprotein subclasses with hepatic fat content. Therefore, we determined the fasting lipoprotein profile and assessed the relationship with visceral and hepatic fat in 101 federally employed women without diabetes (53 African American (AA), 15 African immigrant (AI), 33 white (WW); age 44±9 (mean±SD), range 24- 62y; BMI 30.0±5.5, range 20.3-45.2 kg/m2. Lipoprotein particle number and size were measured with NMR. Percent body fat was assessed by DXA and hepatic and visceral fat by proton magnetic resonance spectroscopy. Compared to AA and WW, AIs were younger (AI: 38±10 vs. AA: 44±8 vs. WW: 46±10y, P<0.05) and leaner (AI: 34±7 vs. AA: 38±6 vs. WW: 39±7% body fat, P<0.05), but there were no ethnic differences in physical activity or dietary fat intake. After adjustment for age and % body fat, compared to WW, AI and AA had lower fasting triglyceride (P<0.001), large VLDL (P<0.01) and medium VLDL (P<0.001) particle number. Small VLDL, total HDL, total LDL particle number and total VLDL particle size were similar among the 3 groups of women (P>0.05). In multivariate linear models, insulin sensitivity, visceral and hepatic fat were independently associated with large VLDL particle number (adjR2=0.53, P<0.001). Medium VLDL particle number was related to African ethnicity, % fat, and insulin sensitivity but not visceral or hepatic fat (adjR2=0.37, P<0.001).

In summary, visceral and hepatic fat were independently associated with fasting triglyceride rich large VLDL particles and contribute to paradoxically normal triglyceride levels in African descent women.


1928‑PEffects of the SGLT2 Inhibitor on Histological Improvement of Non‑alcoholic Fatty Liver Disease Based on Serial Liver BiopsiesCHIZURU WATANABE, NORIO AKUTA, YOSHIYUKI SUZUKI, MASAHIRO KOBAYASHI, HITOMI SEZAKI, KYOHEI HAYASHI, YASUMICHI MORI, HIROMITSU KUMADA, Kanagawa, Japan

Sodium-glucose cotransporter 2 inhibitors (SGLT2I) have been reported to improve accumulation of fat, as well as improving blood glucose, suggesting that SGLT2I may be effective for nonalcoholic fatty liver disease (NAFLD). We examined that liver histological findings (based on biopsy specimens), glucose tolerance and body composition (measured using an INBODY770) were compared between before and after 24 weeks of Canagliflozin (CANA) 100 mg/day treatment in type 2 diabetes patients with NAFLD. Glucose tol-erance were evaluated with sum [Σ] of the Plasma glucose (PG) levels mg/dl and sum [Σ] of the CPR levels ng/ml measured at 0, 60, and 120 minutes after meal tolerance test. NAFLD was evaluated pathologically based on Brunt’s classification and the NAFLD activity score (NAS). Five patients were enrolled in this study (3 men and 2 women aged 57.6±7.9 years, HbA1c8.3±2.1%, BMI 26.7±2.4 and the duration 10.8±6.8 years). We found that the each mean difference between after and before was HbA1c -0.7 (0.4)%, Σ PG −80 (46.8) mg/dl and Σ CPR -5.1 (3.2) ng/ml. Improvement of insulin resistance was observed in 4 patients. Also the loss of total body weight (TBW) (SD) was -3.7 (1.6) kg. The loss of skeletal muscle mass accounted for at least 40% of TBW loss in one patient in whom insulin resistance was not improved. His-tological examination demonstrated improvement of the following findings after CANA treatment: steatosis in all patients, lobular inflammation in one patient, ballooning in 2 patients [disappearance of ballooning in one patient], and fibrosis stage in 2 patients. Thus, hepatocellular fatty change and the NAS score improved in all patients, and improvement of fibrosis stage was also observed in 2 patients. The NAS score improved by at least 2 points without progression of fibrosis stage (complete response) in 2 patients.

A511


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



2nd being a combination of factors including oxidative stress. The kelch-like ECH-associated protein 1(Keap1)/nuclear factor E2-related factor 2 (Nrf2) pathway is the major regulator of cytoprotective responses to oxidative stress. In the basal state, Keap1 sequesters Nrf2 in the cytoplasm; however, in the presence of oxidative stress, Keap1 releases Nrf2 into the nucleus where it can activate a battery of antioxidant genes. In this study, we pre-fed a western diet to male C57BL/6 mice for 5 months to induce NASH and then dosed control and Keap1 antisense oligonucleotides (ASO) for an additional 12 weeks. Keap1 ASO significantly reduced liver Keap1 mRNA (-91% vs. con-trol ASO) and protein levels, which increased hepatic mRNA expression of the Nrf2 target genes NAD(P)H quinone dehydrogenase1 and glutathione S-transferase alpha1 relative to control ASO treatment. Mice administered the Keap1 ASO had significantly lower plasma ALT concentrations and liver steatosis. These changes were due in part to reductions in liver lipogenic mRNA expression (Fasn, Srebp1c and Acc1). Keap1 ASO also reduced liver fibrosis as evidenced by reductions in hydroxyproline concentrations, as well as reductions in Collagen type I alpha 1, Collagen type I alpha 2, Tissue inhibitor of metalloproteinases1 and Tissue inhibitor of metalloproteinases 2 mRNA expression relative to control ASO. Furthermore, Keap1 ASO had no effect on cardiac Nrf2 target gene expression or plasma B-type natriuretic peptide, a marker of heart failure. These data suggest that antisense inhibi-tion of Keap1 may be a promising, safe therapeutic approach for the preven-tion of diet-induced NASH.

1933‑PMolecular Mechanism for the Hypoglycemia Associated with Jamaican Vomiting SicknessYANG QIU, DANIEL F. VATNER, RACHEL J. PERRY, XIAN MAN ZHANG, GARY W. CLINE, GERALD I. SHULMAN, Shenyang, China, New Haven, CT

Ingestion of unripe ackee fruit is the cause of the Jamaican Vomiting Sickness, which can lead to hypoglycemia and death. Hypoglycin A is the hypoglycemia-inducing toxin of unripe ackee fruit, and methylenecyclopro-pylacetic acid (MCPA) is the active metabolite of Hypoglycin A; however the molecular mechanism by which MCPA causes hypoglycemia in vivo has not been established. To address this question we administered MCPA (80 mg-kg-1 IV) to awake SD rats along with stable isotopes to assess rates of glucose turnover and assessed hepatic gluconeogenic fluxes by a novel positional isotopomer NMR distribution analysis method. Following MCPA administration, rates of endogenous glucose production (EGP) decreased by 46% (P<0.001 compared to vehicle treated). Reduction in rates of beta-oxi-dation was reflected by an 82% decrease in rate of β-hydroxybutyrate turn-over (P<0.05) and resulted in an 83% reduction in liver acetyl CoA concentra-tion (P<0.0001). The fractional contribution of pyruvate carboxylase (PC) flux to EGP was reduced (Vehicle: 0.53±0.03; MCPA: 0.14±0.01; P<0.0001), and absolute PC flux was markedly reduced (Vehicle: 13.1±1.6; MCPA: 0.6±0.1 μmol/kg-min; P<0.0001). Notably, with the exception of acetyl CoA, hepatic short chain CoAs increased in concentration (in particular, a 20-fold increase in butaryl CoA was observed, P<0.0001). Previous in vitro work suggested that MCPA was primarily a medium chain acyl CoA dehydrogenase inhibitor, while these in vivo data demonstrate that MCPA’s major effect to decrease hepatic acetyl CoA content is through inhibition of short chain acyl CoA dehydrogenase.

Conclusion: Taken together these data demonstrate that the hypoglyce-mia associated with unripe ackee fruit ingestion can be ascribed to MCPA-induced reductions in hepatic gluconeogenesis, which can be attributed to inhibition of short chain CoA dehydrogenase activity leading to reductions in hepatic acetyl CoA content and pyruvate carboxylase activity.

1934‑PMetabolic Effects of One Week of Heavy Drinking and Fast‑Food Intake during Roskilde Festival 2016 in Young Healthy Male AdultsMIA DEMANT, SIGNE FOGHSGAARD, MALTE P. SUPPLI, LISE GETHER, MARTIN THOMASEN, NIELS B. DALSGAARD, LÆRKE S. GASBJERG, SIGRID BERGMANN, AMALIE R. LANNG, MAGNUS F. GRØNDAHL, KRISTIAN H. MIKKELSEN, SR., CHARLOTTE STRANDBERG, MERETE KØNIG, MARTIN KRAKAUER, HENNING GRØNBÆK, ULRIK BECKER, JOACHIM KNOP, NICOLAI J. WEWER ALBRECHT-SEN, JENS JUUL HOLST, TINA VILSBØLL, FILIP K. KNOP, Hellerup, Denmark, Aar-hus, Denmark, Hvidovre, Denmark, Frederiksberg, Denmark, Copenhagen, Denmark

Metabolic effects of intermittent unhealthy lifestyle in otherwise young healthy adults are poorly studied. We investigated the effect of one week’s unhealthy lifestyle on glucose metabolism and liver parameters in a group of young, healthy males participating in Roskilde Festival 2016. Festival par-ticipants (FP) (n=13, age: 24.3±2.0 years (mean±SD), BMI: 23.3±2.5 kg/m2) were studied before and after participation (one week) in Roskilde Festival

metabolism remains incompletely understood. To investigate whether SIRT1 plays a role in berberine’s salutary effects in the liver during nutrient over-load, liver-specific SIRT1 knockout (SIRT1 LKO) mice were fed with a high fat, and high sucrose (HFHS) diet, followed by administration with berberine. In WT mice, berberine induced autophagy as evidenced by reduced conversion of LC3-I to LC3-II levels and quantification of autophagic vesicles, and led to attenuation of hepatic steatosis. Strikingly, berberine-mediated effects were largely diminished in SIRT1 LKO mice. Berberine caused an induction of LC3-II levels in the liver treated with autophagy inhibitor chloroquine, suggesting an induction of autophagic flux by berberine. Moreover, SIRT1 deficiency abrogated berberine-mediated augmentation of LC3-II levels and reduction of steatosis in livers during fasting, further supporting the essen-tial role of SIRT1 in the control of hepatic autophagy and lipid homeostasis. In SIRT1-/- primary hepatocytes or MEFs, berberine-induced expression of LC3-II was diminished. Consistently, berberine-reduced lipid accumula-tion was abolished by a pharmacological SIRT1 inhibitor EX527 in HepG2 cells treated with palmitate. These results suggest that SIRT1 is required for berberine to induce autophagy and repress lipid accumulation in a cell-autonomous manner. Mechanically, berberine stimulates SIRT1 activity and induces autophagy by deacetylating a key autophagic gene Atg5. Our find-ings indicate that berberine acts as an activator of SIRT1 in the liver, and SIRT1 activation of autophagy has the therapeutic potential for treating obesity-related disorders, such as fatty liver diseases and type 2 diabetes.

Supported By: National Natural Science Foundation of China (81270930, 31471129, 31671224)

1931‑PRole of a Jmjd3‑SIRT1 Complex in Epigenomic Regulation of Energy MetabolismSUNMI SEOK, BYRON KEMPER, JONGSOOK KIM KEMPER, Urbana, IL

Epigenomic regulation is critical for maintaining homeostasis during nutrient and hormonal fluctuations. Jmjd3 histone demethylase (KDM6B) epigenomically activates genes in development and differentiation, but its role in metabolism remains unknown. SIRT1 deacetylase mediates fasting responses by activating fatty acid β-oxidation and gluconeogenic genes, but SIRT1-mediated gene activation mechanisms are poorly understood. Here we show that jmjd3 is a gene-specific transcriptional partner of SIRT1 and mediates epigenomic activation of SIRT1-target β-oxidation genes, but not gluconeogenic genes, during fasting. Proteomic, genomic, and biochemical studies revealed that fasting-induced jmjd3, working together with SIRT1 and PPARα, epigenomically upregulates β-oxidation promoting genes, including FGF-21 and Cpt1, but not gluconeogenic genes. Liver-specific downregulation of jmjd3 decreased β-oxidation and induced fatty liver and glucose/insulin intolerance. Expression of jmjd3 and SIRT1 was low in obesity, and restoration of jmjd3 or SIRT1 levels improved fat oxidation and glucose/insulin tolerance in a mutually dependent manner. A SIRT1-jmjd3 complex identified in this study may serve as an effective drug target for obesity and diabetes by selectively lowering lipid levels without detrimen-tally increasing glucose levels.

Figure.

Supported By: American Diabetes Association (1-16-IBS-156 to J.K.K.); National Institutes of Health (DK062777, DK095842)

1932‑PAntisense Oligonucleotides Targeting Keap1 Protect Mice from Diet‑Induced NASHWUXIA FU, RICHARD LEE, MARK GRAHAM, AMY WEI, STAN RINEY, ROSANNE CROOKE, Carlsbad, CA

Nonalcoholic steatohepatitis (NASH) is liver disease characterized by steatosis, inflammation, and hepatocellular damage. The pathogenesis is thought to occur via a two-hit mechanism, the first being steatosis and the

A512


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



Results: In the total population, PWV correlated with liver elastometry (p<0.004), and similarly in the normotensive patients (p<0.04) but not the hypertensive patients. Liver fibrosis was detected in 24 T2Ds (14%) and 8 OB (14.2%). PWV was 8.5±2.2m/s in T2Ds and 7.8±2.0m/s in OB. PWV was >RV in 10 hypertensives (8.8%, 8 T2Ds and 2 OB) and in 25 normotensives (44.6%, 12 T2Ds and 13 OB). Among hypertensive patients 19 (16.7%, 18 T2Ds and 1 OB) had liver fibrosis, PWV was >RV in 2 and ≥8m/s in 9 of these 19 patients. Among normotensive patients 13 (11.7%, 6 T2Ds and 7 OB) had liver fibrosis, PWV was >RV in 5 and ≥8m/s in 10 of these 13 patients (77%).

Conclusion: Liver fibrosis as detected by elastometry affects 14% of T2Ds and nondiabetic OB. Arterial stiffness is less prevalent among hypertensive patients, probably due to current treatment. A PWV≥8m/s which is not the threshold defining artery stiffness can identify 77% of the normotensive patients with liver fibrosis according to elastometry.

1937‑PPrimacy of Indirect Control by Insulin of Endogenous Glucose Pro‑duction via FFA: Single‑Gateway Hypothesis RevisitedMALINI S. IYER, RICHARD N. BERGMAN, Los Angeles, CA

The mechanisms regulating endogenous glucose production (EGP) are not fully understood. In 1956 Irving Fritz and Rachmiel Levine suggested that insulin was not a direct controller of liver EGP. Early evidence supporting the indirect regulation of hepatic EGP came from our lab. We found that the rates of EGP suppression were similar whether insulin was administered intraportally or systemically. These rates were also similar to the rates of glucose appearance in the interstitium and glucose uptake by peripheral tis-sues; suggesting that the site of insulin action was extra-hepatic. We pro-posed the ‘single-gateway hypothesis’: the rate-limiting transport of insulin across the adipose tissue capillaries is responsible for the slow suppression of FFAs which in turn is responsible for delayed suppression of EGP during insulin infusion. We showed that preventing the fall in plasma FFAs during insulin infusion either by administering intralipids or by inhibiting lipolysis, led to failure in EGP suppression, supporting our hypothesis. More recently 2 independent groups (Lu et al., 2012, Titchenell et al., 2016 and Perry et al., 2015) demonstrated that in mice lacking hepatic FoxO1 and Akt (L-Akt-FoxO1TKO), required for insulin signaling, glycemia was normal. Inhibiting the fall of plasma FFAs in these mice prevented the suppression of EGP dur-ing a clamp. Measuring whole body turnover rates of glucose and FFAs in L-AktFoxO1TKO mice also confirmed that hepatic EGP was regulated by insu-lin mediated control of FFAs. Data from several investigators using insulin receptor (IR) KO mice (LIRKO), IR and FoxO1 KO mice (LIRFKO), L-AktFoxO1TKO and in vitro studies together suggest that hepatic FoxO1 is central to the indirect regulation of EGP by insulin. The KO models along with our physi-ological findings confirm the single-gateway hypothesis which states that insulin moment-to-moment normalization of EGP is mediated indirectly via suppression of lipolysis in adipose tissue.

1938‑PPreventive Effects of Bitter Melon (Momordica Charantia) against NAFLD Is Associated with a Reduction in the ER‑Stress Pathways in HepG2 Cells and High Fat/High Fructose‑Fed MiceSO YEON AN, HWAJOUNG LEE, SUNG-E CHOI, RIHUA CUI, JA YOUNG JEON, YUP KANG, TAE HO KIM, SEUNG JIN HAN, HAE JIN KIM, DAE JUNG KIM, KWAN WOO LEE, Seoul, Republic of Korea, Suwon, Republic of Korea

Momordica charantia L. fruit (bitter melon) improves glucose and lipid homeostasis and insulin resistance in vivo, but the exact mechanism in the liver and hepatocytes has not been well studied. In this study, we investi-gated the protective molecular mechanism of bitter melon in inflammation and death of HepG2 cells and nonalcoholic fatty liver disease (NAFLD) in high fat/high fructose-fed mice. To clarify the effects of bitter melon on inflam-mation and death of the cells, we treated HepG2 cells with palmitate and measured several signaling pathways such as inflammation, endoplasmic reticulum (ER)-stress, and cell death by immunoblotting. To investigate the effects of bitter melon on NAFLD, C57BL/6J were randomly divided into three groups: low-fat diet (LFD) control group, 60% high fat and 30% high fructose diet group, and HF/HF plus ethanol-extracted bitter melon diet group. Body weight, food intake, and plasma glucose were documented for 12 weeks. We demonstrated that bitter melon was significantly effective for ameliorating HF/HF diet-induced glucose intolerance, insulin resistance, liver weight, and liver triglycerides. In addition, bitter melon significantly reduced liver inflam-mation at the protein and mRNA levels. To investigate the molecular mecha-nism of bitter melon, we tested several signal pathways using immunoblot-ting. Interestingly, bitter melon significantly increased chaperone proteins, such as binding protein and calnexin, whereas it reduced palmitate-induced

2016 and matched with controls (n=14, age: 24.4±1.6 years, BMI: 23.4±2.2 kg/m2) who lead a normal life for an equivalent period of time. An oral glu-cose tolerance test (OGTT), abdominal ultrasound and strain elastography for liver stiffness were performed. The FP group consumed more alcohol compared to a week of standard living conditions preceding the festival (2±4 vs. 16±8 units/day, P<0.001). Area under curve (AUC) for glucose dur-ing OGTT did not change during the intervention in either of the groups, but C-peptide responses increased in the FP group (206±42 vs. 236±65 nmol/L × min, P=0.05) and, correspondingly, Matsuda index of insulin sensitivity was diminished (6.2±2.4 vs. 5.0 ±1.4, P=0.05). The AUC for glucagon increased in the FP group (1,037±324 vs. 1,562±702 pmol/L × min, P=0.003) together with fasting fibroblast growth factor-21 (FGF-21) (62±30 vs. 132±72 pmol/L, P<0.001) and aspartate aminotransferase levels (36±8 vs. 42±11 U/L, P=0.04). Four (31%) developed ultrasound-detectable steatosis and mean liver stiffness increased (P=0.05) in the FP group. Participation in Roskilde Festival 2016 was associated with diminished insulin sensitivity, increases in glucagon, FGF-21 and liver enzyme levels, and led to ultrasound-detect-able hepatic steatosis in a substantial proportion of participants along with increased degree of liver stiffness.

1935‑PNonalcoholic Fatty Liver Disease and Type 2 Diabetes Mellitus Are Associated via Visceral Fat AccumulationSHINYA FUKUMOTO, MASANORI EMOTO, KOKA MOTOYAMA, TOMOAKI MORIOKA, KATSUHITO MORI, TETSUO SHOJI, NORIFUMI KAWADA, KAZUTO HIRATA, MASAAKI INABA, Osaka, Japan

Nonalcoholic fatty liver disease (NAFLD) is considered to be a risk factor for the onset of type 2 diabetes mellitus (T2D), but no studies have consid-ered the role of visceral fat (VF), which is strongly linked to both NAFLD and T2D, as a potential confounder. Therefore, it is not clear how NAFLD and T2D are associated. In this study, we quantitatively measured the extent of intrahepatic fat accumulation using the controlled attenuation param-eter (CAP) to explore the direct associations of intrahepatic fat accumula-tion with both concurrent T2D and the risk for developing T2D. Among the recipients of health check-ups who had their CAP value and visceral fat area (VFA) measured at our health center, those who consumed excessive alcohol were excluded, leaving 331 subjects (156 men, 47.1%; mean age, 57.3 years). To assess the risk for developing T2D, the 49 T2D patients were excluded from the aforementioned subjects. CAP values were obtained using the FibroScan® 502 Touch. The high-risk group for developing T2D was defined as those with a 33-54% chance of developing T2D within 3 years based on the risk scores previously reported. After adjusting for the influences of other factors by multivariate logistic regression analysis, we examined the associations of T2D with CAP values and VFA separately. The results showed that the risk for concurrent T2D increased by 9.5% for every 10 dB/m increase in CAP and by 17.1% for every 10 cm2 increase in VFA. However, when CAP and VFA were analyzed within the same model, only VFA was a statistically significant risk factor. Likewise, the risk for being in the high-risk group for developing T2D increased by 20.2% for every 10 dB/m increase in CAP and by 40.4% for every 10 cm2 increase in VFA. When CAP and VFA were analyzed within the same model, only VFA was a significant risk factor.

In conclusion, the association between NAFLD and concurrent T2D or the risk for developing T2D may not be direct, but rather via the influence of VF accumulation.

1936‑PArterial Stiffness Measurement Is Useful to Screen Patients with Type 2 Diabetes or Obesity for Liver FibrosisAMEL REZKI, MARINOS FYSEKIDIS, SABRINA CHIHEB, ISABELA BANU, CAMILLE PILLEGAND, YAHYA JABER, EMMANUEL COSSON, PAUL VALENSI, Bondy, France

Aim: Nonalcoholic fatty liver disease is a marker or factor of cardiovas-cular risk. The aim was to assess the predictive value of arterial stiffness, an early indicator of atherosclerosis, for liver fibrosis in patients with type 2 diabetes (T2D) and obese patients without known diabetes (OB).

Patients and Methods: We included 225 patients (53.5±12.6 years, BMI 32.4±12.5 kg/m², 114 with well-controlled hypertension, 169 T2Ds, 56 OB), free of liver disease, alcohol abuse and cardiovascular history. All had valid measurements of liver fibrosis (Fibroscan®) and carotid-femoral pulse wave velocity (PWV) (applanation tonometry, Sphygmocor®). Liver fibrosis was defined by elastometry ≥8kPa, and high arterial stiffness by PWV >refer-ence value (RV: established for age and blood pressure status, Reference Values for Arterial Stiffness’ Collaboration, 2010) or ≥mean PWV level (8m/s) in our population.

A513


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



1941‑PHepatic APOA4 Promotes Toxin‑Induced Liver Injury and Inflamma‑tionWANGSHU QIN, JIANAN LIU, LINNA JIA, XIAOYUE CHEN, XINZHI LI, XIAOMENG REN, ZHENG CHEN, Changchun, China

Obesity is a growing health problem all over the world. Nonalcoholic fatty liver diseases (NAFLD) is strongly associated with obesity, which increases the sensitivity of liver to acute liver injury. APOA4 expression has been shown to be abnormally elevated in the obese liver. Whether APOA4 is associated with liver injury and inflammation is largely unknown. Here we demonstrate that APOA4 is induced by liver injury and further promotes liver injury and inflammation. Both mRNA and protein levels of APOA4 are significantly increased in damaged liver. Liver-specific knockdown of APOA4 significantly ameliorates CCl4-induced liver injury, inflammation, and oxi-dative stress. Furthermore, knockdown of APOA4 in primary hepatocytes decreases inflammatory-related gene expression. These data demonstrates that abnormal accumulation of APOA4 promotes liver injury and inflamma-tion, providing a novel mechanism by which NAFLD increases the suscepti-bility of liver to toxin-induced liver injury.

Supported By: People’s Government of Jilin Province (2013046); Jilin Science and Technology Development Program (20160101204JC); Jilin Talent Development Foundation (111860000); National Natural Science Foundation of China (31500957, 31671225)

1942‑PLiver‑Specific Overexpression of Gamma‑Glutamyltransferase Ameli‑orates Insulin Sensitivity of Male C57BL/6 MiceTAO CHEN, YANG LONG, JINYU SHI, HAOMING TIAN, Chengdu, China

Recently, several prospective studies and meta-analysis suggested that gamma-glutmyltransferase (GGT), a previously recognized marker of alco-holic drinking and fatty liver, was associated with increased risk of type 2 diabetes (T2D). In the clinical setting, GGT elevation usually accompanied by other T2D risk factors such as ferritin, uric acid and markers of chronic inflammation. These factors could mask the genuine relationship between GGT and T2D. In the current study, we developed a liver specific GGT-overexpressing mice model and investigated the effects of GGT eleva-tion on glucose metabolism and insulin sensitivity. Transgenic mice model in C57BL/6 background were built up by rapid injection pLIVE-GGT vector through tail vein according to the method of hydrodynamic delivery. The serum GGT activity was significantly increased after 7 days of pLIVE-GGT1 vector delivery, and lasted for about 3 weeks. Liver specific overexpression of GGT reduced the levels of GSSG and GSH in the liver and serum, and had no effects of total antioxidative capacity in the liver, kidney, skeletal muscle except pancreas. Increased GGT activity had no effect on the glucose toler-ance, but could facilitate blood glucose lowering after intraperitoneal insulin administration. The results of Western blotting showed that increased GGT activity enhanced insulin-induced AKT phosphorylation at Ser473. Further-more, GGsTop™, a selective GGT inhibitor, could attenuated the changes of insulin induced blood glucose uptake and AKT phosphorylation in liver. Taking together, these results indicated that GGT elevation in a short term had no effects on glucose metabolism, but could increase insulin sensitivity through enhancing activity of insulin signaling pathway. These results sup-ported the notion that GGT elevation could be a protective factor rather than an offending factor to T2D.

Supported By: National Natural Science Foundation of China (81100572)

1943‑PBariatric Surgery Enhances Postprandial Hepatic Blood Flow Response in Morbidly Obese Subjects with Type 2 DiabetesHENRI HONKA, JUKKA KOFFERT, SAILA KAUHANEN, NOBU KUDOMI, SAIJA HURME, ANDREA MARI, ANDREAS LINDQVIST, NILS WIERUP, LEIF GROOP, PIRJO NUUTILA, Turku, Finland, Kagawa, Japan, Padua, Italy, Malmö, Sweden

Meal ingestion provokes an increase in the superior mesenteric artery blood flow (BF) accommodating nutrient absorption and metabolism. We have previously shown that glucose-dependent insulinotropic polypeptide (GIP) contributes to this postprandial splanchnic BF redistribution. Here, we investigated the effects of mixed-meal testing and GIP infusion on hepatic vasculature in a total of 10 morbidly obese subjects with type 2 diabetes (T2D) before and two months after bariatric surgery (Roux-en-Y gastric bypass and vertical sleeve gastrectomy, both n=5), and 10 lean age-matched controls. Portal vein blood flow (PVBF) and hepatic blood volume (HBV) were quantitated using positron emission tomography coupled with radiotracers [15O]radiowater and [15O]carbon monoxide, respectively. Bariatric surgery resulted in a partial T2D remission in eight subjects, decreases in HOMAIR

ER-stress signaling, such as phosphoeIF2α, CCAAT/enhancer binding pro-tein homologous protein, and phospho-c-JunN-terminal kinase in palmitate-treated HepG2 cells. Similar effects were shown in HF/HF diet mice. This is the first report demonstrating that bitter melon has protective effects on NAFLD by reducing ER stress in HepG2 cells and HF/HF-diet mice. Therefore, it may be useful for the prevention of NAFLD.

1939‑PBeneficial Effects of the TAZ Modulator TM‑25659 on Palmitate‑Induced Lipogenesis in HepG2 Cells and Fatty Livers from DIO and MCD‑Diet‑Fed MiceKWAN WOO LEE, JONG GAB JUNG, SUNG-E CHOI CHOI, TAE HO KIM, JA YOUNG JEON, YUP KANG, MYUNG AE BAE, JIN HEE AHN, HANA JEONG, EUN SOOK HWANG, SO YEON AN, SEUNG JIN HAN, HAE JIN KIM, DAE JUNG KIM, Suwon, Republic of Korea, Seoul, Republic of Korea, Gwangju, Republic of Korea

The transcriptional co-activator with PDZ-binding motif (TAZ) modulator (TM-25659) inhibits adipocyte differentiation by interacting with peroxi-some proliferator-activated receptor gamma (PPARgamma). In this study, we investigated the beneficial effects of TM-25659 and the molecular mechanism of palmitate-induced lipogenesis in HepG2 cells and in the fatty liver of DIO and mice fed a HF completely devoid of methionine and cho-line diet (MCD). We treated the cells and mice with TM-25659 and used mRNA sequencing to evaluate the expression of transcription factors such as PPARgamma, retinoid X receptor, and nuclear receptor corepressor 1 (NCOR1), as well as gene expression-related lipogenesis and inflammation. Glucose homeostasis and insulin sensitivity were evaluated after 16 weeks of treatment in the HF diet mice and after 4 weeks in the MCD mice. Fasting insulin and serum lipid levels were measured at the end of the study. Genes involved in inflammation and lipid metabolism were analyzed by real-time PCR and immunoblotting. Body weight, fasting insulin, and plasma glucose were maintained in the TM-25659-treated group. We demonstrated that TM-25659 was significantly effective for ameliorating HF diet-induced glu-cose intolerance, insulin resistance, and fatty liver. In addition, TM-25659 significantly reduced hepatic steatosis and immune cell infiltration. TM-25659 also reduced fatty liver in MCD mice as well as the expression of several inflammation-related genes. TM-25659 led to TAZ nuclear localiza-tion and binding with transcription factors, such as PPARgamma and NCOR1, in HepG2 cells. Finally, TM-25659 inhibited palmitate-induced inflammatory cytokine and lipogenic gene expression in HepG2 cells. This is the first report demonstrating that TM-25659 has protective effects on NAFLD through the enhanced interaction between TAZ and PPARgamma. Therefore, TM-25659 may be useful for preventing NAFLD.

1940‑PChREBP Mediates Metabolic Adaptation to Fructose Intake and Prevents Fructose‑Rich Diet‑Induced HepatotoxicityDEQIANG ZHANG, XIN TONG, GRAHAM BRADY, ZHUOXIAN MENG, JIANDIE D. LIN, LIANGYOU RUI, BISHR OMARY, LEI YIN, Ann Arbor, MI

Background: Epidemiologic and animal studies implicate overconsumption of fructose in the development of nonalcoholic fatty liver disease. However, the molecular pathways that allow mammals to adapt to fructose-rich diet remain largely unknown.

Results: We present evidence supporting the essential function of the lipogenic transcription factor ChREBP in adaptation to fructose and pro-tection against fructose-induced hepatotoxicity. High-fructose diet (HFrD) activated hepatic lipogenesis via a ChREBP-dependent manner in wild type mice, while inducing steatohepatitis in ChREBP-KO mice. In ChREBP-KO mouse livers, HFrD reduced levels of molecular chaperones and activated the CHOP-dependent unfolded protein response (UPR), whereas administra-tion of chemical chaperone or Chop shRNA reversed liver injury. Restoring ChREBP or chaperone GRP78 rescue HFrD induced liver injury in ChREBP-KO mice. Gene expression profiling revealed elevated expression of cholesterol biosynthesis genes in ChREBP-KO livers after HFrD. Furthermore, inhibi-tion of cholesterol biosynthesis by atorvastatin or Srebp2 shRNA reduced hepatic CHOP expression and rescued liver injury in HFrD-fed ChREBP-KO mice. Mechanically, ChREBP inhibits cholesterol biosynthesis by both sup-pressing Srebp2 transcription and accelerating SREBP2 protein degradation.

Conclusion: Our findings demonstrate a pivotal role of ChREBP in hepato-protection against HFrD by preventing overactivation of cholesterol biosyn-thesis and CHOP-mediated pro-apoptotic UPR.

Supported By: National Institutes of Health (DK099593 to L.Y.)

A514


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



resistance, it could have a central role in the progression from steatosis to NASH. We have established a diet induced rodent model of NASH for the evaluation of CHOP inhibition in a diseased state. A pilot study demon-strated increases in the ER stress response after feeding C57 mice for 24 weeks with AMLN diet. Mice were then treated with Saline, Control ASO or CHOP ASO for eight weeks at 25 mpk/wk. CHOP ASO treated mice devel-oped less liver fibrosis as indicated by lower expression of fibrotic genes as well as liver hydroxyproline (Control ASO, 3.21 ± 0.88; CHOP ASO, 2.22 ± 0.7 vs. Saline, 3.13 ± 1.17 μmol/g) as compared to control ASO group. This data suggests that CHOP plays an important role in NASH disease progression and targeting CHOP may be a novel approach for the treatment of NASH.

1946‑PIntegrative Genomic Analyses to Understand the Common and Sex‑Specific Mechanisms Underlying Nonalcoholic Fatty Liver DiseaseKARTHICKEYAN CHELLA KRISHNAN, ZEYNEB KURT, SIMON SABIR, RAQUEL FLOYD, XIA YANG, ALDONS J. LUSIS, Los Angeles, CA

Nonalcoholic fatty liver disease (NAFLD) is an umbrella term encompass-ing a range of liver abnormalities from simple liver steatosis, a condition where there is an excessive accumulation of triglycerides in liver cells which then disrupts normal liver function, to complex nonalcoholic steatohepa-titis (NASH), cirrhosis, and liver cancer. NAFLD is the most common form of chronic liver disease with poorly understood etiology and differential prevalence between sexes. To understand the causal molecular mechanisms and underlying sexual dimorphisms in NAFLD, we integrated genome, tran-scriptome, and phenotype data derived from a population-based approach from both males and females of over 100 different strains of inbred mice subjected to high-fat, high-sucrose (HF/HS) diet for 8 weeks, using a com-putational approach. The pathways perturbed during NAFLD include lipid metabolism and synthesis (especially fatty acids and cholesterols), growth factor signaling, immune reactions, oxidation reactions, cell cycle, cellular transport, branched chain amino acid degradation, post-translational protein modifications, extra cellular matrix and glycoproteins, and insulin signaling. We observed that the male tissues (adipose and liver) had more pathways related to lipid metabolism than the female tissues, which is consistent with the clinical data showing that males are more affected by NAFLD. Next, we used the key driver analysis (KDA) process to define hub or key regulator genes within the male hepatic TG associated pathways. As proof of concept, we targeted and validated four possible key regulator genes of this complex disease, namely, CHCHD6, FASN, PKLR and THRSP using in vivo adenovi-ral shRNA knockdown in mice. Lastly, we compared our mouse data-driven findings with the previously identified 107 candidate NAFLD-associated. We observed a strong consistency between our results and previously studied genes and mechanisms.


1947‑PHepatic Insulin Extraction in Nonalcoholic Fatty Liver Disease Is Related to Insulin Resistance Rather than Liver Fat ContentKRISTINA M. UTZSCHNEIDER, RICHARD N. BERGMAN, STEVEN E. KAHN, DAVID POLIDORI, Seattle, WA, Los Angeles, CA, San Diego, CA

Nonalcoholic Fatty Liver Disease (NAFLD) is associated with obesity and type 2 diabetes. Insulin clearance affects circulating insulin levels, which are elevated in obesity and insulin resistance. While total insulin clearance is decreased in NAFLD, the relationship between liver fat and hepatic insulin extraction is not known.

We studied 28 subjects without diabetes, 13 with NAFLD (9M/4F) and 15 controls (8M/7F) matched for age (mean±SD: 50±8 NAFLD vs. 51±7 y con-trols) and BMI (33±4 vs. 33±5 kg/m2). Subjects had a CT scan to estimate liver fat (liver/spleen ratio, L/S), a hyperinsulinemic-euglycemic clamp and an oral glucose tolerance test (OGTT). Hepatic and extra-hepatic insulin clear-ance were estimated using data from the clamp and OGTT and a recently developed mathematical model of insulin kinetics. Insulin secretion rates estimated from C-peptide levels were combined with known clamp insulin infusion rates to estimate clearance parameters.

Subjects with NAFLD had increased liver fat as expected as demon-strated by a lower L/S (mean±SEM: 0.76±0.06 NAFLD vs. 1.22±0.04 con-trols, p<0.001). Fasting glucose was higher in NAFLD (106±3 vs. 96±2 mg/dl, p=0.005), but A1c did not differ (5.6±0.1 vs. 5.7±0.1%). Insulin sensitivity was lower in NAFLD (rate of glucose disposal (Rd): 4.2±0.4 vs. 7.0±1.1 mg/min/kg FFM, p=0.03). Extra-hepatic insulin clearance did not differ (9.3±0.9 vs. 8.8±1.1 ml/min/kg FFM, p=0.7). Hepatic insulin extraction was similar at baseline (51±3.8 vs. 53±2.9%), but during the OGTT tended to be lower in NAFLD at all time points starting 20 minutes after glucose ingestion

(P=0.001) and liver volume (P<0.001), and an increase in beta cell glucose sensitivity (P=0.048). During the mixed-meal testing GLP-1 and glucagon responses and insulin secretion were enhanced after bariatric surgery when compared to pre-surgery values (all P<0.001), whereas GIP response was similar in all studied groups. PVBF remained unchanged (P=0.131) and HBV decreased by 50.8 (40.3-102) mL (P<0.001) in all studied groups. When post-surgery data was analyzed separately, PVBF was raised 1.65-fold from base-line (P=0.026), with no difference between the surgical groups. Infusion of exogenous GIP did not change PVBF (P=0.837) in any group but reduced HBV by 72.3 (56.6-149) mL (P<0.001) in all subjects after surgery.

In summary, PVBF response to a mixed-meal is enhanced after bariatric surgery, mediating rapid delivery of nutrients and hormonal signals to liver. Mixed-meal decreases HBV similarly in lean and obese subjects, suggesting redistribution of blood to extrahepatic sites. GIP influences the HBV response to a mixed-meal particularly after surgery with little effect on PVBF.

Supported By: Academy of Finland; Finnish Cultural Foundation; Finnish Medical Foundation

1944‑PReduced Hepatic Insulin Clearance Is More Pronounced in Obese Subjects Independent of the Degree of HyperglycemiaAMALIA GASTALDELLI, MELANIA GAGGINI, RALPH A. DEFRONZO, San Antonio, TX, Pisa, Italy

Insulin resistance (IR) and β-cell dysfunction are the main physiologic dis-turbances which underly the transition from normal glucose tolerance (NGT) to type 2 diabetes mellitus (T2DM). The liver is the primary site of insulin degradation and in glucose intolerance states the metabolic clearance rate of insulin (MCRI) is reduced resulting in peripheral hyperinsulinemia. This serves as an important compensatory mechanism to maintain normal glucose tolerance. The aim of this analysis was to identify the physiologic mechanisms that are associated with reduced MCRI.

We studied 365 subjects (52 nonobese and 48 obese NGT; 63 obese IGT, 67 nonobese and 135 obese T2DM). Subjects received euglycemic insulin clamp (IC) with 3-3H-glucose and 75g oral glucose tolerance test (OGTT). We calculated MCRI (IC insulin infusion/steady state plasma insulin conc), Hepatic-IR (fasting EGP x FPI), Adipocyte-IR (fasting plasma FFA x FPI), peripheral-IR (1/(Matsuda index) and (M/I)-1), β-cell function (DI/DGOGTT÷IR), fasting and OGTT insulin secretion rate (ISR, from c-peptide deconvolution).

MCRI was significantly reduced in obese NGT, IGT and T2DM (509±17, 534±15 and 525±12 ml/kg min, p<0.005) vs. nonobese NGT and T2DM (628±21 vs. 620±19 ml/kg min). MCRI was inversely correlated with periph-eral-IR (r=-0.43), Hep-IR (r=-0.45), Adipo-IR (r=-0.39) (all p<0.0001), with fast-ing ISR and OGTT ISR (both r=-0.25, p<0.0001) and DI/DG (r=-0.17, p<0.005). No correlation was found between MCRI vs. β-cell function [DI/DG÷IR], FPG, 2h-PGOGTT or HbA1c. In multivariate analysis, after accounting for age, gen-der and BMI, increased DI/DG and peripheral-IR remained independently correlated with MCRI (partial r=-0.29 and r=-0.43 respectively).

Conclusions: Reduced MCRI is more pronounced in obese vs. nonobese subjects, in both nondiabetic and T2DM. The decrease in MCRI is strongly related to the severity of IR and impairment in insulin secretion and is inde-pendent of the degree of hyperglycemia.

1945‑PEvaluation of Antisense Oligonucleotide against CHOP in Rodent Models with ER Stress DysfunctionSANG JUN LEE, SUSAN F. MURRAY, SHULING GUO, BRETT P. MONIA, Carlsbad, CA

A malfunction of the ER stress response caused by aging, genetic muta-tions, or environmental factors can result in various diseases such as dia-betes, inflammation, and neurodegenerative disorders. To alleviate such a stressful situation, eukaryotic cells activate a series of self-defense mechanisms referred to collectively as the ER stress response. CHOP is a transcription factor that plays an essential role in ER stress-induced apop-tosis. We identified an antisense oligonucleotide (ASO) targeting CCAAT/enhancer-binding protein homologous protein (CHOP). To evaluate the func-tion of CHOP after exposure to tunicamycin (TN), mice were pretreated for 2 weeks with Saline, Control ASO or CHOP ASO. The treatment of CHOP ASO prevented the induction of CHOP mRNA levels as compared to saline treat-ment (Saline (TN), 36 fold; CHOP ASO (TN), 3 fold vs. normal Saline control). Moreover CHOP ASO treatment effectively reduced liver steatosis and tri-glyceride content. Increased activation of the ER stress response has been reported in obese mice and human as well as NASH patients (GASTROEN-TEROLOGY 134, 568-76 2008; Science 306, 457-61 2004). Because the ER stress response is a critical mediator of inflammation, apoptosis and insulin

A515


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



1950‑PDifferences in Peripheral and Hepatic Insulin Resistance between Lean Healthy South Asian and Chinese MenHONG CHANG TAN, TONG WEI YEW, SHAJI CHACKO, E. SHYONG TAI, JEAN P. KOVALIK, JIANHONG CHING, SANDI M. THANT, CHIN MENG KHOO, Singapore, Singapore, Houston, TX

Lean South Asian men have greater insulin resistance compared to eth-nic counterparts matched for body weight. However, it remains unclear whether peripheral insulin sensitivity or hepatic insulin resistance is pre-dominantly affected. Metabolic “inflexibility” and abnormal branched-chain amino acids (BCAA) metabolism may also play a role. Our study compared peripheral insulin sensitivity, hepatic insulin resistance, metabolic flexibility, and plasma BCAA between 13 healthy and lean South Asian and 13 Chinese men matched for ethnicity, age, BMI and body fat percentage. All subjects underwent hyperinsulinemic-euglycemic clamp and targeted metabolomic profiling. South Asian males had higher hepatic insulin resistance index (159.4 ± 15.0 vs. 127.2 ± 11.1 μmol/kgFFM/min. μU/ml, p=0.096) and required significantly higher blood insulin concentration (111.7 ± 5.8 vs. 96.5 ± 3.7 μU/ml, p =0.038) to produce similar suppression endogenous glucose pro-duction duing insulin clamp compared to Chinese. By contrast, peripheral insulin sensitivity (57.6 ± 6.0 vs. 62.2 ± 6.9 μmol/kgFFM/min), metabolic flex-ibility (DRQ 0.06 ± 0.01 vs. 0.05 ± 0.1) and fasting plasma BCAA (383.38 ± 12.16 vs. 360.05 ± 10.94 μM) were similar (p > 0.05). Fasting blood glycine (β = -0.460, p=0.016) and total BCAA (β = -0.408, p=0.032) were significant predictors of peripheral insulin sensitivity but not hepatic insulin resistance.

In conclusion, lean South Asian men had greater hepatic insulin resis-tance but similar peripheral insulin sensitivity and metabolic flexibility as lean Chinese men when matched for both BMI and percent body fat. BCAA and glycine levels are independent predictors of peripheral and not hepatic insulin resistance.

Supported By: Australian National Health and Medical Research Council (NMRC/CG/013/201)

1951‑PEffect of Liver Transplantation on Beta‑Cell Function and Insulin Sensitivity and Clearance in Cirrhotic Patients: A Two‑Year Follow‑Up StudyVALERIA GRANCINI, MARIA LINDA BOSELLI, MARIA ELENA LUNATI, EVA PALM-IERI, VERONICA RESI, RICCARDO BONADONNA, EMANUELA ORSI, Milan, Italy, Verona, Italy, Parma, Italy

Abnormalities of glucose (G) homeostasis are common in cirrhotic patients and may improve after liver transplantation (LT). We assessed beta cell func-tion (BCF) and insulin (I) sensitivity/clearance in 89 cirrhotic patients, who were studied before and 3, 6, 12, 24 months after LT by a frequently sampled OGTT, which was analyzed by well-established mathematical models and provided 4 key outputs: 1. derivative control (DC: I secreted in response to the rate of plasma G increase; units: [pmol·m-2 BSA]/[mM·min-1]) and 2. propor-tional control (PC: the stimulus-response curve linking G per se to I secretion rate) of BCF from the G/C-peptide curves; 3. OGIS (units: ml.min-1.m-2 BSA), a robust index of I sensitivity, from the G/I curves; 4. I Clearance (units: L.min-1.m-2 BSA) from the combined analysis of G/C-peptide/I curves. After LT, 26 patients recovered from DM (regressors, R), 15 did not (non-regres-sors, NR), 4 developed DM, and 44 stayed nondiabetic. Before LT, R group was similar to NR group, but for higher I sensitivity (OGIS 373.65±91.85 vs. 316.51±82.82, p=0.048). In all groups I clearance increased (p<0.03) from 1.3±0.2 (before LT) to 1.9±0.1, 1.8±0.1, 1.7±0.2 and 1.6±0.1 before and 3, 6, 12, 24 months after LT, respectively. In the R group, the trajectories over time of I sensitivity (from 367±92 to 435±62 to 432±73 to 423±54 to 449±62) and DC of BCF (from 522±142 to 965±282 to 1207±238 to 1572±360 to 1309±287) showed significant improvements in the R group only (p=0.0001 and p=0.001, respectively). A declining trajectory over time of PC of BCF was detected in the NR group (p<0.05-0.01).

In conclusion, LT brings about a generalized increase in I clearance and is associated to regression of DM in ~30% of patients. Our data ascribe this beneficial change in G homeostasis to improvements in both I sensitivity and specific facets of BCF.

(p ≤0.1). Extra-hepatic insulin clearance did not correlate with BMI, L/S or Rd. Hepatic insulin extraction over the OGTT positively correlated with Rd (r=0.59, p=0.001) but was not associated with BMI or L/S. We conclude that in NAFLD hepatic insulin extraction is related to decreased insulin sensitivity rather than liver fat content itself.

Supported By: U.S. Department of Veterans Affairs

1948‑PMild Physiologic Hyperglycemia Induces Hepatic Insulin Resis‑tance in Healthy Normal Glucose‑Tolerant SubjectsDEVJIT TRIPATHY, AURORA MEROVCI, MARIA ESCOBAR VASCO, ANDREA HAN-SIS-DIARTE, MUHAMMAD ABDUL-GHANI, RALPH A. DEFRONZO, San Antonio, TX

The aim of the present study was to evaluate effect of a physiologic increase in plasma glucose concentration on endogenous glucose produc-tion (EGP) in healthy NGT individuals. 16 NGT subjects: 8 with family history of T2DM (FH+((5M/3F, age = 47± 14 yrs, BMI = 27 ± 1 kg/m2) and 8 without FH (FH-) (4M/4F, Age = 42±9, BMI = 26±1) participated in a 3-step hyperinsu-linemic (10, 20, 40 mU/m2·min) euglycemic clamp before and after a 48 hour glucose infusion to increase plasma glucose conc by ~50 mg/dl above base-line. Endogenous glucose production was measured with [3-3H] glucose and gluconeogenic rate was measured as (EGP) (plasma C5/C2 glucose ratio) dur-ing infusion of deuterated water. FPG concentration increased from 97±4.5 to 140±4.9 mg/dl following 48 hours of glucose infusion while basal EGP increased from 2.05±0.09 to 3.06±0.29 mg/kg·min (p=0.003) and hepatic insulin resistance index (EGP X Fasting Plasma Insulin) increased markedly and similarly (20.1±1.8 vs. 51.7± 6.6, p<0.005) in FH+ and FH- subjects. Fol-lowing chronic glucose infusion, the rate of gluconeogenesis (5.58± 1.8 vs. 5.78±2.06 μmol/kg·min) remained unchanged and the rate of glycogenolysis (total EGP minus gluconeogenic rate) increased (6.55± 3.3 to 8.25±2.4 μmol/kg·min, p<0.10). Thus, both increased glycogenolysis and gluconeogenesis contributed to the increase in basal EGP following chronic glucose infusion. Total body insulin sensitivity declined from 8.75±2.1 to 6.92± 6 mg.kg/min (p<0.05) during the 40 mU/m2·min insulin clamp. Chronic (48 hr) physiologic hyperglycemia to levels seen in T2DM increases basal endogenous (hepatic) glucose production and induces hepatic and skeletal muscle insulin resis-tance in healthy NGT subjects. These results demonstrate, for the first time, that glucotoxicity causes resistance to the suppressive effect of insulin on hepatic glucose production.

1949‑PNovel Polymorphisms in ApoB and PCSK9 Genes of Familial Hyper‑cholesterolemic TALLYHO/Jng MiceEUN AH LEE, DONG IN LEE, SANG DAL RHEE, Daejeon, Republic of Korea

Objective: TALLYHO/Jng (TH) mouse is a polygenic type 2 diabetes (T2D) model developed in the Jackson Laboratory. It has hyperleptinemia, hyperin-sulinemia, hyperlipidemia, and hypercholesterolemia. However, TH mice are unknown the cause of the hypercholesterolemia. To understand the cause of hypercholesterolemia in TH mice, we performed whole exome sequencing with TH genomic DNA (gDNA) in the tail.

Methods: The intact gDNA from TH and C57BL/6 (B6) mice were puri-fied from mouse tails using the ReliaPrep™ gDNA Tissue Miniprep System (Promega) according to the manufacturer’s guidelines. The whole exome sequencing was performed that it uses clonal amplification and sequencing by DNA polymerase, and each base emits a unique fluorescent signal, which is used to determine the order of the DNA sequence by using SureSelect XT Mouse Exon kit. The expression levels of ApoB, and Pcks9, were examined by immunoblot analysis in the plasma and liver compared to B6 mice as nor-mal control.

Results: 79,950 of variants were identified from whole exome of the TH mice. It was analyzed the genetic variations in the genes of cholesterol metabolism, such as cholesterol synthesis (12 genes), cholesterol transport (25 genes) and bile acid synthesis (11 genes), in which 30 missense and nonsense variants were recognized. There were no polymorphisms in cho-lesterol synthetic genes. There was some novel 2 polymorphisms of P168L and V1481I in a cholesterol transporting protein, ApoB and 3 polymorphisms of G200A, R305Q and R534H in the Ldl receptor inhibitor, PCSK9. It was also founded that expression levels of the ApoB and PCSK9 proteins were decreased in the plasma, but not in the liver of TH mice. Those data sug-gested that normal functions of ApoB and PCSK9 might be changed.

Conclusion: The novel polymorphisms of ApoB and PCSK9 might be causes of hypercholesterolemia in TH mice.

A516


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



glucose and energy metabolism, conditional liver specific mINDY knockout mice (L-INDY-KO) were generated by crossing INDY fl/fl mice with albumin Cre-recombinase transgenic mice. After 10 weeks on HFD (60% KCal from fat), body weight and composition was similar between L-INDY-KO and age matched littermate INDY fl/fl mice. Oxygen consumption during the day (6000±200 ml/h/lean mass L-INDY-KO vs. 5400±150 ml/h/lean mass, P=0.02) and the respiratory quotient (0.77±0.01 L-INDY KO vs. 0.75±0.01, P<0.01) were increased in L-INDY-KO mice, despite reduced locomotor activ-ity during the night. Hyperinsulinemic euglycemic clamp studies revealed improved overall insulin sensitivity in L-INDY-KO mice (GINF: 18±0.1 mg/Kg/min L-INDY-KO vs. 14±0.1 mg/Kg/min, P=0.04), and increased overall glycogen synthesis (10.6±1.4 mg/Kg/min L-INDY-KO vs. 6,6± 2.3 mg/Kg/min, P=0.001). Together, these data show that mINDY is an important factor in the regulation of glucose and energy homeostasis. mINDY may be an interesting target for the treatment of insulin resistance and type 2 diabetes.

Supported By: Boehringer Ingelheim

1955‑PThe Diabetes‑Resistance Variant of mt‑Nd2 Prevents Mitochondrial Dysfunction during NAFLDGABRIEL A. FERNANDEZ-BUENO, KAITLYN I. ABDO, SRILAXMI KALAVALAPALLI, PAIGE N. ANDREWS, NISHANTH E. SUNNY, CLAYTON E. MATHEWS, Gainesville, FL

Over 70% of patients with type 2 diabetes mellitus (T2DM) have nonalco-holic fatty liver disease (NAFLD). The metabolic signatures during disease progression, and role of mitochondria (mt) in the pathogenesis of NAFLD is poorly understood. A genetic variant of mt-Nd2 has previously shown to con-fer resistance to both type 1 and type 2 diabetes in humans and mouse mod-els. Diabetes resistance has been linked to decreased ROS production. The goal of this study was to determine whether this polymorphism decreases the susceptibility to NAFLD/T2DM. We have used conplastic mouse strains that only differ by a single nucleotide polymorphism in mt-Nd2: the protective mt-Nd2a allele or the common allele, mt-Nd2c. mt-Nd2c and mt-Nd2a males were placed on control or high trans-fat diet (TFD) to assess diabetogenic changes. Presence of mt-ND2a allele blunted the TFD induced elevation in plasma free fatty acids (FFA). Hepatocyte triglyceride levels were similar on control diet (mt-Nd2c:19.62 ± 2.28 vs. mt-Nd2a:15.80 ± 2.83 mg/liver). TFD feeding of the 2 strains produced a significant 2-fold elevation in mt-Nd2c (87.84 ± 5.94) compared to mt-Nd2a mice (44.46 ± 9.38 mg/liver, p<0.01). To establish the effect of FFA overload on insulin signaling, hepatocytes were cultured in 0.2mM or 0.8mM palmitate medium. mt-Nd2c hepatocytes exhib-ited normal insulin signaling, as indicated by P-AKT in low palmitate and a blunted response with high palmitate. In contrast mt-Nd2a hepatocytes displayed robust insulin signaling in low and high FFA. Hepatic tri-carboxylic acid (TCA) cycle flux and mitochondrial anaplerosis also remained lower in mt-Nd2a under TFD when compared to mt-Nd2c. Further, mtROS production was similar in mice on control diet, while mtROS from mt-Nd2c mice on TFD was significantly increased. The biochemical differences observed between the groups suggests that the protective mt-Nd2a variant prevents onset of hepatic steatosis while decreasing TCA cycle flux, anaplerosis and ROS pro-duction in the liver.

Supported By: National Institutes of Health/National Institute of Diabetes and Digestive and Kidney Diseases (R01DK112865)

1956‑P

1952‑PImpact of Three Months Metformin Treatment on VLDL‑TG Metabo‑lism in Healthy Subjects and Patients with Type 2 DiabetesLARS C. GORMSEN, ESBEN SØNDERGAARD, NANA CHRISTENSEN, LARS P. TOLBOD, SØREN NIELSEN, Aarhus, Denmark

Background: Metformin is the most commonly used first-line antidiabetic drug with well documented glucose lowering effects. However, metformin may also lower circulating triglycerides independently of changes in glucose homeostasis. It was therefore an aim of this study to measure whether met-formin inhibits hepatic very-low-density-lipoprotein-triglyceride (VLDL-TG) secretion.

Methods: In a randomized, double-blinded, parallel group study, 24 patients (BMI 30.8 (SD 4.9), age 62 (SD 5)) with type 2 diabetes (T2D) were randomized to either 3 months treatment with 1000 mg metformin bi-daily (MET) or placebo (PLA). 12 healthy age matched (BMI 27.3 (SD 4.1), age 62 (SD 6) subjects treated with 1000 mg metformin bi-daily served as control group (CONT). Patients were studied before initiation of treatment and after completing 3 months treatment. Basal VLDL-TG metabolism was measured by a bolus injection of ex-vivo triolein-labeled [1-14C]VLDL and whole-body glucose metabolism was measured by a constant infusion of [9,10-3H] glu-cose during basal and insulin-stimulated conditions. A linear mixed model was used to assess the impact of time, treatment and time*treatment inter-action.

Results: The MET and PLA group did not differ in diabetes duration, HbA1c, BMI or age. Patients with T2D had significantly greater VLDL-TG Ra compared with healthy controls [82.2 +/- 47.7 vs. 48.6 +/- 41.3, p=0.04) and there was a strong inverse correlation between insulin sensitivity (glucose rd) and VLDL-TG secretion (r=-0.51, p>0.01). Endogenous glucose production decreased after treatment in the MET group compared with PLA and CONT (treatment p=0.04, time*treatment p=0.03). Contrary to our hypothesis metformin treatment did not affect VLDL-TG Ra in patients or controls (time p=0.77, time*treatment p=0.97).

Conclusion: 3 months treatment with 1000 mg metformin bi-daily does not affect hepatic VLDL-TG secretion despite measurable effects on endog-enous glucose production.

Supported By: Danish Council for Independent Research; Augustinus Founda-tion; Danielsens Foundation

1953‑P

1954‑PLiver Specific Deletion of the Mammalian Indy Homolog Amelio‑rates Diet‑Induced Insulin Resistance In MiceDIANA WILLMES, ANICA KURZBACH, MARTIN DANIELS, TINA SCHUMANN, STEFAN BORNSTEIN, STEPHEN HELFAND, ANDREAS L. BIRKENFELD, Dresden, Germany, Berlin, Germany, Providence, RI

Reducing INDY (I’m Not Dead Yet) gene expression increases life span in flies. In mice, deletion of the mammalian INDY homolog (mINDY, Slc13a5) protects mice from diet and aging induced obesity and insulin resistance. mINDY encodes for a plasma membrane transporter of TCA cycle intermedi-ates, with the highest affinity for citrate and it is highly expressed in the liver. To better understand the role of hepatic mINDY in the regulation of

WITHDRAWN

WITHDRAWN

A517


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



1959‑PInhibition of p53 with Pifithrin‑alpha Prevents Diabetes‑Induced Hepatic Inflammatory and Oxidative Injury, Probably via Upregulat‑ing Sirt1‑Nrf2 PathwayLINGBO QIAN, JUNLIAN GU, HONGLEI JI, LU CAI, Louisville, KY, Changchun, China

Upregulation of the tumor suppressor p53 has been reported to medi-ate the diabetic hepatic injury, including oxidative stress and inflammation, leading to steatosis. However, its underlying mechanisms remain unclear. Inverse relationship between Sirt1 signaling and p53 was found in high glu-cose-exposed hepatic cells. Reportedly Sirtuin 1 (Sirt1) triggers the release of nuclear factor erythroid-derived 2-like 2 (Nrf2) into nuclei to activate its target antioxidant genes. The aim of present study was to explore whether the hepatic protection from diabetes by p53 inhibition with pifithrin-alpha is associated with up-regulation of Sirt1-Nrf2 pathway in type 1 diabetic mice. FVB mice were treated with five daily injections of 50 mg/kg strep-tozotocin to induce type 1 diabetes. Both hyperglycemic and age-matched control mice were treated with or without pifithrin-alpha 5 times a week for 2 months and then kept without the treatment for additional 1 month and 4 months. At 3 and 6 months post-diabetes, significantly increased serum ALT activity, hepatic 3-NT, 4-HNE, IL-6 and TNF-alpha expressions were noticed in diabetic mice but not in pifithrin-alpha-treated diabetic mice. The increased expression of p47 phox and decreased expressions of Sirt1 (both in protein and mRNA) and nuclear Nrf2 in the diabetic livers were all reversed by pifithrin-alpha-treatment. Transcriptional levels of Nrf2-target genes HO-1, NQO1 and catalase were markedly enhanced by pifithrin-alpha in diabetic mice. These results demonstrate that the inhibition of p53-medi-ated down-regulation of Sirt1-Nrf2 pathway by treating diabetic mice with p53 specific inhibitor can effectively prevent the development of hepatic inflammatory and oxidative injury.

Supported By: China Scholarship Council (201508330753); National Natural Science Foundation of China (81470495)

1960‑PPhenotypic Analysis of Previously Identified Blood Metabolite GWAS Genes Using Generation 2.5 Antisense OligonucleotidesYING WEI, STAN RINEY, WUXIA FU, STEVE YEH, RICHARD LEE, MARK GRAHAM, ROSANNE CROOKE, Carlsbad, CA

The metabolic syndrome (MetS) is a public healthcare problem character-ized by simultaneous occurrence of obesity with other metabolic abnormali-ties such as hyperglycemia, hypertension or dyslipidemia. The risk of devel-oping MetS depends on synergy of both genetic and environmental factors. Shin et al recently identified 145 genome-wide metabolic loci and their biochemical connectivity with more than 400 metabolites in human blood. In order to better understand the pharmacological consequences of these metabolomics associations, we selected 12 liver-expressed mRNAs which were highly correlated with MetS from list of 145 metabolic loci by using Ionis Gen 2.5 antisense oligonucleotides (ASOs). In this study, C57BL/6 mice were pre-fed with a western diet (diet 88137, 42% fat, 0.2% cholesterol) for 3 weeks and baseline plasma samples were drawn by a retro-orbital bleed to effectively randomize the study cohorts. Two different ASOs for each gene target, used to cross-validate phenotypic observations, were subcutaneously administered at 25 mg/kg/week for 7 doses over 6 weeks. At termination, plasma glucose, lipid and transaminase concentrations were analyzed and liver mRNA expressions were examined. In total, 24 ASOs were identified, that safely and efficiently reduced hepatic mRNA expression by more than 80%. Interestingly, only acyl-CoA dehydrogenase straight chain-specific ASOs reduced downstream plasma triglyceride concentrations up to 50%. Finally, the glutaminase 2-specific ASOs were most effective at reducing total cholesterol and LDL-C concentration in plasma to 72% and 56%, respectively. These promising initial observations provide the impe-tus to further explore their potential benefit in additional metabolic disease models.

1961‑PSuppression of the Murine Gluconeogenic Program by Small Mol‑ecules that Inhibit PGC‑1alpha through Inducing Its AcetylationCLINT D.J. TAVARES, KFIR SHARABI, PERE PUIGSERVER, Boston, MA

Type 2 diabetes mellitus (T2DM) is currently a world-wide epidemic with an urgent medical need for novel antidiabetic drugs. In T2DM chronically ele-vated rates of hepatic gluconeogenesis leads to pathological hyperglycemia and numerous associated co-morbidities. The transcriptional co-activator PGC-1α, that promotes gluconeogenic gene expression and hepatic glucose production, is upregulated in several T2DM rodent models. PGC-1α gluco-neogenic activity is negatively regulated through acetylation. Thus, small

1957‑PThe Role of Hepatic Uncoupling Protein 2 in High‑Fat Diet‑Induced Hyperinsulinemia and Insulin ResistanceCAROLINE E. GEISLER, BENJAMIN J. RENQUIST, Tucson, AZ

The degree of hepatic lipid accumulation, a hallmark of type 2 diabetes, is directly associated with the severity of systemic insulin resistance and hyperinsulinemia. Hepatic lipid accumulation induces expression of uncou-pling protein 2 (UCP2) to limit hepatic lipotoxicity. To understand the role of hepatic UCP2 expression in the development of hyperinsulinemia and insulin resistance, we generated liver specific UCP2 knockout (KO) and control mice (flox, cre, and wt control) by crossing AlbuminCre/+ UCP2flox/+ males to Albu-min+/+ UCP2flox/+ females. We assessed glucose homeostasis at 12-14 weeks of age on a chow diet and again after 6-8 weeks on a high fat diet (60% of kcal from fat) to induce type 2 diabetes. Hepatic UCP2 KO did not alter basal glucose, insulin, glucose:insulin ratio, insulin tolerance, or oral glucose tolerance in chow fed mice (P > 0.05). Additionally, hepatic UCP2 KO did not affect weight gain on the high fat diet (P > 0.05). However, hepatic UCP2 KO prevented the decreased glucose:insulin ratio in obesity (P = 0.03), suggest-ing protection against obesity induced hyperinsulinemia. Hepatic UCP2 KO also improved insulin sensitivity, measured by insulin tolerance test, in diet induced obese mice (P < 0.03). Our data proposes that upregulated hepatic UCP2 expression is integral to the development of obesity induced hyperin-sulinemia and insulin resistance.

Figure.

Supported By: Arizona Biomedical Research Commission (14-082986)

1958‑PAdipose Glucocorticoid Action Modulates Hepatic Insulin Resis‑tance via Alterations in Hepatic Diacylglycerol and PKCε ActivityABUDUKADIER ABULIZI, DANIEL F. VATNER, JOAO-PAULO G. CAMPOREZ, MICHAEL J. JURCZAK, DONGYAN ZHANG, VARMAN T. SAMUEL, GERALD I. SHULMAN, New Haven, CT, Pittsburgh, PA, Hamden, CT

To understand the mechanism by which alterations in adipose glucocorti-coid (GC) action might alter insulin sensitivity, we studied three discrete adi-pose specific genetic mouse models: a) GC receptor knockout (GR-/-); b) 11β hydroxysteroid dehydrogenase type 1 knockout (HSDKO); and c) HSD11B1 transgenic mice (HSDTG). Hyperinsulinemic-euglycemic clamp studies in HFD-fed GR-/- mice revealed protection from HFD-induced whole-body insulin resistance; this difference was entirely accounted for by improved suppression of hepatic glucose production (HGP) (5.6±6.5% vs. 53.7±9.2%, P<0.001). Suppression of plasma nonesterified fatty acids (NEFA) during the clamp was augmented in GR-/- mice (58.2±2.8% WT vs. 71.1±2.0% GR-/-; P=0.01). HSDKO mice were protected from HFD-induced hepatic IR (HGP suppression: 45.6±1.9% WT vs. 89.1±18.6% GR-/-; P<0.05). HSDTG mice dem-onstrated increased HFD-induced hepatic IR (HGP suppression: 37.7±6.6% WT vs. 9.8±8.5% HSDTG; P=0.01). Furthermore, hepatic triglycerides were decreased by 36% (P<0.05) in GR-/-; decreased by 30% (P<0.05) in HSDKO; and increased by 51% (P<0.05) in HSDTG. Hepatic diacylglycerol (DAG) con-tent was decreased by 39% in GR-/- (P<0.05) and increased by 73% in HSDTG (P<0.01), while hepatic ceramide levels were unchanged in both models. DAG mediates hepatic IR via PKCε activation; hepatic PKCε translocation was decreased by 45% in GR-/- (P<0.05) and increased by 40% in HSDTG (P<0.05). Reversal of hepatic steatosis and normalization of hepatic DAG-PKCε activ-ity in HSDTG with a controlled release liver-targeted mitochondrial protono-phore normalized hepatic insulin responsiveness.

Conclusion: These data demonstrate that alterations in adipose GC action impact hepatic insulin action, in part by regulating hepatic DAG content and PKCε activation.

A518


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



pionate, [2H2]water, and 6-6[2H2]glucose) techniques to hepatocyte-specific ILK knockout (hILK-KO) mice. We show a significant increase in endogenous rate of glucose appearance (EndoRa) and glucose utilization in hILK-KO mice. This increase in EndoRa is derived from gluconeogenic sources. The higher glucose utilization occurs despite a lower blood glucose indicating that frac-tional glucose turnover is also accelerated. Underlying a lower 5 h fasting blood glucose in hILK-KO mice was a reduction in glycogen stores after a 5 h fast and impaired glycogen repletion after an 18 h fast, 6 h refeed regimen. Deficient glycogen repletion after a refeed occurred despite no differences in Akt or Gsk3β protein content or phosphorylation statuses. Interestingly, glycogen synthase content was ~4 fold higher in hILK-KO mice and had a decreased inhibitory phosphorylation ratio compared to wild types.

In conclusion, ILK increases glucose utilization while decreasing glycogen storage in the liver, suggesting an acceleration of glycolysis. We speculate that accelerated gluconeogenesis is necessary to prevent hypoglycemia due to low liver glycogen. Therefore, hILK-KO alters hepatic metabolic program-ming causing a dramatic shift in glucose handling, which may be relevant to metabolic disorders associated with ECM remodeling.

Supported By: National Institutes of Health (5T32DK007563, 265R37DK050277, 182U2CDK059637-16)

1964‑PGlycine N‑methyltransferase Regulates Hepatic Glucose Metabo‑lism via Energy Homeostasis in Fasted and Diet‑Induced Obese MiceCURTIS C. HUGHEY, DEANNA P. BRACY, E. PATRICK DONAHUE, DAVID H. WASSERMAN, Nashville, TN

Diet-induced obese (DIO) mice and NAFLD patients display reduced liver glycine N-methyltransferase (GNMT). GNMT regulates levels of the bio-logical methyl-donor, S-adenosylmethionine (SAMe). The influence of GNMT and SAMe homeostasis on dysregulated hepatic nutrient metabolism, com-monly associated with DIO and NAFLD, is largely unstudied. Here we used metabolomics and a method to quantify hepatic glucose fluxes in conscious mice. GNMT KO and WT mice were divided into low fat (LFD) or high fat (HFD) diet groups (n=15-20/group). [6,6-2H2]glucose, 2H2O, and [U-13C3]propionate were infused intravenously in catheterized, fasted mice. Data in parentheses are mean±SEM presented as LFD-WT vs. LFD-KO or HFD-WT vs. HFD-KO. Hepatic SAMe was elevated in LFD-KO mice (0.38±0.03 vs. 403.72±19.52 arbitrary units). Blood glucose was reduced in LFD-KO (7.1±0.3 vs. 5.8±0.1 mmol/L). Hepatic glucose production (HGP) was lower in LFD-KO mice (81±3 vs. 68±5 μmol/kg/min) owing to reduced gluconeogenic flux from PEP (50±2 vs. 40±2 μmol/kg/min). This was associated with an accumula-tion of citric acid cycle intermediates, depressed anaplerosis via pyruvate carboxylase (PC) and reduced cataplerosis through PEPCK. ADP, a PC inhibi-tor, was elevated in LFD-KO livers (2.1±0.1 vs. 7.3±0.3 μmol/g). On a HFD, blood glucose (7.6±0.6 vs. 6.4±0.3 mmol/L) and HGP (62±2 vs. 64±2 μmol/kg/min) were comparable. In contrast to a LFD, anaplerosis and cataplerosis were actually elevated in HFD-KO mice. Hepatic ADP levels were modestly elevated in HFD-KO mice (2.2±0.0 vs. 3.7±0.1 μmol/g). However, HFD-KO mice appear to display systemic alterations in energy metabolism as they were resistant to DIO (35±1 vs. 28±1 g) and had lower plasma insulin levels (1.4±0.4 vs. 0.3±0.1 ng/ml).

In conclusion, GNMT may regulate glucose homeostasis through bio-energetics. Moreover, we hypothesize glucose metabolism is influenced differently by GNMT KO on a LFD (hepatic energetics) and HFD (systemic energetics).

Supported By: National Institutes of Health; Canadian Diabetes Association

1965‑PRegulation of Hepatic Glucose, Lipid, and Energy Metabolism by a FoxO/Adipose Triacylglycerol Lipase (ATGL)/Sirtuin NetworkWENWEI ZHANG, JOSEPH ZAPATER, CLARA BIEN, MARA MASHEK, JOSEPH T. BASS, DOUGLAS G. MASHEK, TERRY UNTERMAN, Chicago, IL, Minneapolis, MN, St. Paul, MN

FoxO1, the major FoxO transcription factor expressed in the liver, pro-motes intrahepatic lipolysis and fatty acid oxidation via the regulation of adipose triacylglycerol lipase (ATGL) and its inhibitor, the G0/S1 switch gene 2 (G0S2), and ATGL plays a critical role in mediating effects of FoxO proteins on hepatic glucose and lipid metabolism (Cell Rep 15:349, 2016). Since ATGL promotes activation of sirtuin 1 (Diabetes 64:418, 2015), which deacetlyates FoxO1 and enhances its binding to DNA target sites, we asked whether ATGL-dependent effects on sirtuin activity contribute to effects of FoxO1 in the liver. Here, we report that nuclear sirtuin activity is increased in transgenic mice expressing constitutively active (Akt resistant) FoxO1 in

molecules that induce PGC-1α acetylation could potentially be used to con-trol systemic blood glucose levels. Using a novel high-throughput chemical AlphaLisa screen, we have recently identified a few compounds that inhibit PGC-1α with the potential of ameliorating diabetic symptoms. Compound 18 suppressed gluconeogenic gene expression and glucose production in primary hepatocytes, while augmenting intracellular concentrations of Ace-tyl CoA and activating the PGC-1α acetyltransferase GCN5 through specific lysine acetylation on K721 and K830. Compound 80 (C-80) potently sup-presses fasting blood glucose in high-fat-diet fed mice and suppresses dia-betic symptoms. Mechanistically, C-80 altered H3K4Me3 and H3K9Ac his-tone marks and reduced HNF4α binding at gluconeogenic gene promoters. PubChem suggests the serotonin receptor as one of the potential targets of C-80, thus we tested the efficacy of the commercially available 5HT2B sero-tonin receptor antagonist LY-266097. LY-266097 strikingly represses induc-tion of the gluconeogenic program in primary hepatocytes, and furthermore reduces fasting blood glucose in high-fat-diet fed mice. Further studies to elucidate the mechanisms underlying the inhibition of PGC-1α-mediated gluconeogenesis by these inhibitors, are currently underway. These studies have an important implication in understanding basic mechanisms of glu-cose metabolism and the treatment of T2DM.

Supported By: American Diabetes Association (1-16-PDF-111 to C.D.J.T.); American Heart Association (15POST22880002); National Institutes of Health (R03DA032468, R01DK069966)

1962‑PObesity Activates Liver XO to Deplete Purines Including AMP, Impair AMPK, and Promote Dysglycemia and Liver SteatosisGIULIO R. ROMEO, MARIA E. SOARES MARTINS DOS SANTOS, YOSUKE SHIKAMA, JONGSOON LEE, STEVEN E. SHOELSON, Boston, MA, Divinópolis, Brazil, Obu, Japan

Insulin resistance (IR) and T2D often associate with fatty liver disease. To investigate potential mechanisms, we used unbiased metabolomics to profile steatotic livers of high fat diet (HFD, 60% fat) fed mice. Compared to chow controls, HFD liver showed increased uric acid (UA) and statistically significant decreases in purine metabolites upstream of xanthine oxidase (XO), including AMP. XO-catalyzed formation of UA is the final and rate-lim-iting step in purine metabolism. We found XO activity elevated by 100% in liver and 50% in epididymal fat (eWAT) of HFD mice. We therefore hypoth-esized that heightened XO activity not only contributes to the established increases in UA seen in obesity and T2D but also accounts for tissue purine depletion seen in our metabolomics studies. Depleted AMP in particular could result in impaired activation of AMPK, a key nutrient sensor thought to be dysregulated in T2D. We found that HFD decreased AMPK activity ~60% in mouse liver and eWAT (P<0.001; n=8). We further tested the inverse rela-tionship between XO and AMPK activities using in vivo methods for loss and gain of XO function. Antisense oligonucleotides (ASO) reduced XO activity by >90% in HFD liver and eWAT, which also restored AMPK activity to lean levels and ameliorated HFD-induced glucose intolerance (GTT AUC ASO-XO 227 ± 19 vs. control 298 ± 36 mg/dl·min; P<0.0001; n=7). Conversely, increas-ing XO activity in HFD liver by adenovirus (Ad)-mediated XO overexpression exacerbated purine depletion, including a 35% decrease in AMP (Ad-XO vs. Ad-GFP; P<0.01; n=4). Enhanced XO activity led to impaired AMPK activity, and worsened IR and liver steatosis. We conclude that obesity upregulates XO activity, thus depleting tissue purine stores, including AMP. Reduced AMP suppresses AMPK activity to promote both liver steatosis and IR. These studies suggest that XO inhibitors, which are routinely used to treat gout, may help to restore AMPK responsiveness and glucose tolerance in T2D patients.

Supported By: American Diabetes Association (1-15-BS-11 to J.L.); National Institutes of Health

1963‑PHepatic Integrin‑Linked Kinase Determines Glucose Homeostasis through a Specific Glucose Partitioning ProgramELIJAH TREFTS, ASHLEY S. WILLIAMS, CURTIS C. HUGHEY, AMBRA POZZI, ROY ZENT, DAVID H. WASSERMAN, Nashville, TN, Durham, NC

Insulin resistance (IR) is a primary obesity-related pathology. Hepatic IR associates with loss of insulin’s inhibitory effects on hepatic glucose output, and correlates with extracellular matrix (ECM) expansion. Integrin receptors relay physical and biochemical signals from the ECM to control a number of cellular processes. We have recently established that Integrin-Linked Kinase (ILK) contributes to glucose tolerance and insulin sensitivity, but its contribu-tion to glucose flux regulation has not been described. To test the hypothesis that ILK regulates hepatic glucose fluxes we applied stable isotope ([13C3]pro-

A519


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


INTEGRATED PHYSIOLOGY—MACRONUTRIENT METABOLISM AND FOOD INTAKE

Luseo or vehicle was delivered before administration of glucose or 2-DG. (Study 2) Luseo or vehicle was not delivered before it. Furthermore, mRNA expression related with glucose absorption and incretin in each part of intestine were examined. (Study 1) During OGTT, Luseo lowered blood glu-cose and insulin levels at 15 min. before accelerating urinal glucose excre-tion. Plasma total GIP level at 15 min. was lower and GIP levels at 60-120 min. were higher in Luseo group. Plasma GLP-1 levels at 15-120 min. were higher in Luseo group. Intestinal 2-DG uptake in Luseo group was 13% smaller in duodenum, but was 25-30% larger in jejunum and ileum. (Study 2) 2-DG uptake in all parts of small intestine were elevated by 30-40% in Luseo group. SGLT1, GLUT2 and GIP mRNA expression was higher in Luseo group in duodenum and jejunum. Proglucagon mRNA expression in all parts of small intestine was increased in Luseo group. Plasma GLP-1 levels during OGTT were higher in Luseo group.

In conclusion, Luseo affected intestinal glucose absorption after single-dose or chronic administration. Chronic treatment with Luseo increased intestinal glucose absorption by upregulating glucose transporter expres-sion.

1968‑PCardiomyocyte Specific SIRT1 Deficiency Alters Glucose Metabo‑lism in Response to Ischemic InsultsLIN WANG, COURTNEY CATES, JI LI, Jackson, MS

SIRT1 is a conserved NAD+-dependent protein deacetylase. AMP-acti-vated protein kinase (AMPK) is an energy sensor. AMPK and SIRT1 signal-ing pathways have common activators such as caloric restriction, oxidative stress and exercise. It is hypothesized that aging-related impaired ischemic AMPK activation and increased susceptibility to ischemic insults are due to a decreased SIRT1 levels in aging. Mice were subjected to ligation of left anterior descending coronary artery for in vivo ischemic models. The glucose and fatty acid oxidation were measured in a working heart perfu-sion system. The cardiac functions by echocardiography show no difference in young (SIRT1flox/flox), aged (SIRT1flox/flox) and young inducible cardiomyocyte specific SIRT1 knockout (icSIRT1 KO) mice under physiological conditions, but after ischemia and reperfusion, the ejection fraction of aged and icSIRT1 KO mice were impaired. The aged and icSIRT1 KO hearts vs. young hearts also show an impaired post-ischemic contractile function in Langendorff perfusion system. The immunoblotting data demonstrated that aged and icSIRT1 KO hearts vs. young hearts had impaired phosphorylation of AMPK and downstream GLUT4 translocation during ischemia. Intriguingly, AMPK upstream LKB1 is hyper-acetylated in both aged and icSIRT1 KO hearts that could blunt activation of LKB1, leading to an impaired AMPK activation. The working heart perfusion results demonstrated that SIRT1 deficiency signifi-cantly impair substrate metabolism in the hearts, fatty acid oxidation is aug-mented and glucose oxidation is blunted during ischemia and reperfusion. Furthermore, AMPK agonist A769662 treatment can rescue the tolerance of aged heart but not icSIRT1 KO hearts to ischemic insults. Therefore, cardiac SIRT1 mediates AMPK activation via LKB1 deacetylation during ischemia. SIRT1 and AMPK agonists have therapeutic potential for treatment of aging-related ischemic heart disease.

Supported By: American Diabetes Association (1-14-BS-131, 1-17-IBS-296 to J.L.); National Institutes of Health

1969‑PEffects of 72‑Hours Fasting and Refeeding on Fat Oxidation and Weight SuppressionSHO ENDO, KAZUTOSHI MIYASHITA, ASUKA UTO, MASAAKI SATO, CHIKAKO FUJII, MASANORI MITUISHI, HIROSHI ITOH, Tokyo, Japan

Background: Intermittent fasting (IF) has been shown to have benefits on health including an increase in insulin sensitivity and stress resistance. However, the mechanism for the beneficial effects has not been elucidated yet.

Design and Method: Mice were subjected to 4 weeks of a severe IF regi-men, in which they were fasted for the first 72-hours and then refed ad libi-tum for the remaining 96-hours. This course was consecutively repeated 4 times to enforce the effects. After 4 courses of the IF regimen, mice were fed a high-fat diet (HFD) ad-libitum for subsequent 4 weeks. Body weight (BW) and rectal temperature (RT) were monitored throughout the study period. At the 2 different time-points: just after the 4 weeks of the IF regimen and after ad-libitum feeding for 4 weeks subsequent to the IF periods, the glucose tolerance and respiratory gas were analyzed.

Result: There was no significant difference in BW and RT between the adlib eating and IF groups just after 4 weeks of the IF regimen. Glucose tol-erance tests showed a significant decrease in the glucose level of IF group.

the liver (Tgn) compared to wild type (WT) mice and adenoviral knockdown (KD) of ATGL reverses this effect. Conversely, the level of acetylated FoxO1 relative to total FoxO1 is reduced in Tgn vs. WT, and ATGL KD increases acetylated FoxO1 levels in both Tgn and WT mice, consistent with changes in sirtuin activity. Further, ChIP assay shows that ATGL KD reduces FoxO1 occupancy on the IGFBP1 promoter, a canonical FoxO1 target gene, consis-tent with changes in FoxO1 acetylation. Total histone 3 acetylation (AcH3K9) also is markedly reduced in Tgn vs. WT mice and restored by ATGL KD, sug-gesting that ATGL and sirtuins also may mediate effects of FoxO1 on global chromatin remodeling. HPLC analysis revealed that changes in sirtuin activ-ity are not due to differences in NAD+ levels in Tgn vs. WT mice. However, ATP levels are reduced by ~50% in freely fed Tgn vs. WT mice, and restored by ATGL KD. Conversely, ATP levels are suppressed to a similar extent by fasting in WT mice and this effect is blunted in liver-specific FoxO knockout mice. These results indicate that FoxO proteins, ATGL and sirtuins function together to regulate gene expression and modulate glucose, lipid and energy metabolism in the liver.

Supported By: U.S. Department of Veterans Affairs; National Institutes of Health

1966‑PWide Interindividual Variation of First‑Pass Hepatic Insulin Extrac‑tion and Its Association with Whole‑Body Insulin Sensitivity in a Healthy Dog PopulationISAAC ASARE BEDIAKO, REBECCA L. PASZKIEWICZ, STELLA P. KIM, ORISON O. WOOLCOTT, MIGUEL BURCH, MARILYN ADER, RICHARD N. BERGMAN, Los Angeles, CA

Insufficient insulin to stimulate glucose uptake and inhibit endogenous glucose production is one of the underlying mechanisms in the pathogenesis of diabetes. Circulating insulin is a function of pancreatic beta cell secre-tion and metabolic insulin clearance (hepatic and extrahepatic extraction of the hormone). The liver is the principal organ of insulin extraction and its dominance of insulin metabolism is due to the first-pass hepatic extraction (FPE). After secretion into the portal vein, insulin transits the liver to access systemic circulation and exert its action on target organs. In this first-pass, ~50% of the secreted insulin is extracted. Using the dog model, we exam-ined the interindividual variability of FPE and insulin sensitivity. In healthy dogs (n=17), FPE was directly measured by the paired portal/peripheral insu-lin infusion clamp (PPII). PPII consisted of insulin infused intraportally at 3 graded rates and blood sampled peripherally for insulin measurements. In the paired experiment, separated by 3 days, insulin was infused at half that of portal rates, also sampled peripherally. FPE was calculated as the dif-ference in insulin clearance rates between the paired experiments. Insulin clearance rate was calculated from the slope of insulin infusion vs. plasma insulin. Whole-body insulin sensitivity (Si) was estimated using the hyperin-sulinemic euglycemic clamp (EGC). There was ~3.5-fold range (22.35-77.17%) in FPE with a mean of 52.73% ± 16.10% (SD), consistent with the generally accepted ~50% FPE. The range of Si was also wide (1.95-26.23 x 10-4 dl/min/pM) with a mean of 6.86 ± 5.71 x 10-4 dl/min/pM (SD). Importantly, there was a significant correlation between FPE and Si (r = 0.52, p = 0.03).

In conclusion, we found a wide interindividual variation of FPE and Si. FPE could be an important determinant of whole-body insulin action.



1967‑PEffects of Luseogliflozin on Intestinal Glucose Absorption in Dia‑betic Mice: Upregulation of Glucose Transporter Expression by Chronic Treatment with LuseogliflozinMASASHI SHIMODA, ATSUSHI OBATA, TOMOHIKO KIMURA, TOMOE KINOSHITA, KENJI KOHARA, SHUHEI NAKANISHI, TOMOATSU MUNE, KOHEI KAKU, HIDEAKI KANETO, Kurashiki, Japan

Although urinary glucose excretion by sodium glucose cotransporter 2 (SGLT2) inhibitor is maintained for extended period, the underlying mecha-nism for maintaining glucose homeostasis is still unknown. Here, we show that SGLT2 inhibitor affects intestinal glucose absorption after single-dose or chronic administration. We used 10-week-old obese diabetic db/db mice. (Study 1) In single-dose administration, the mice orally received 3 mg/kg of luseogliflozin (Luseo) or vehicle (control). (Study 2) In chronic treatment, the mice in Luseo group received standard chow containing 0.0025% Luseo for 2 weeks. We examined oral glucose tolerance test (OGTT) and intestinal 2-deoxy-D-glucose (2-DG) uptake under the following conditions; (Study 1)

A520


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



1971‑PThree Days Low‑Carbohydrate/High‑Fat Diet Increases Insulin Clearance in Nonobese Healthy MenRURIKO SUZUKI, YOSHIFUMI TAMURA, SAORI KAKEHI, KAGEUMI TAKENO, YUKO SAKURAI, TAKASHI FUNAYAMA, YASUHIKO FURUKAWA, HIDEYOSHI KAGA, DAISUKE SUGIMOTO, SATOSHI KADOWAKI, YUKI SOMEYA, AKIO KANAZAWA, RYUZO KAWAMORI, HIROTAKA WATADA, Tokyo, Japan

It has been reported that 1-wk overfeeding impairs insulin sensitivity and elevates insulin level, and the latter is partly induced by impaired metabolic clearance rate of insulin (MCRI). Thus, MCRI is considered as a regulatory fac-tor to maintain euglycemia during short term dietary change. However, the effect of low-carbohydrate/high-fat (LCHF) diet on MCRI has not been eluci-dated. To clarify the effect of 3-day LCHF diet, we studied 48 nonobese healthy men (BMI; 22.6±2.5 kg/m2). Each subject consumed a 3-day control diet, which was followed by a 3-day eucaloric LCHF diet (20% carbohydrate, 20% protein, 60% fat). After the completion of both diet protocols, we performed hyperin-sulinemic euglycemic clamp (insulin infusion rate (IIR) = 100 mU/m2 per min) to evaluate glucose infusion rate (GIR) and MCRI, calculated as a ratio of IIR to steady state serum insulin (SSSI). The 3-day LCHF diet increased MCRI (497.4±71.4 ml/min per m2 to 540.1±85.0 ml/min per m2, P < 0.05); however, the individual changes were highly variable. To further investigate the role of MCRI, we divided the subject into high-responder (HR) and low-responder (LR) based on the median % change of MCRI by LCHF diet. At baseline, HR group showed higher GIR level compared with LR group (13.0±1.9 vs. 11.8±2.0 mg/kg FFM per min, P<0.05), while MCRI and SSSI levels were comparable. After LCHF diet, MCRI was increased (481.9±58.8 to 582.5±90.8 ml/min per m2, P<0.001) and SSSI was decreased (210.2±23.3 μU/mL to 175.1±23.5 μU/mL, P<0.001) in HR group, but those were not altered in LR group. In parallel with decreased SSSI, GIR was decreased in HR group (from 13.0±1.9 to 11.7±2.4 mg/kg FFM per min, P=0.003) after LCHF diet, but not in LR group.

In conclusion, MCRI was increased after 3-day LCHF diet; however, the effect was highly variable. The decreased GIR after LCHF diet in HR group may be partly due to decreased SSSI and contribute to maintain euglycemia during low-carbohydrate availability in insulin sensitive subjects.


1972‑PImpact of Gastrointestinal pH in Patients with Type 1 Diabetes Using the Wireless Motility CapsuleCHRISTINA BROCK, ANNE-MARIE LANGMACH WEGEBERG, BIRGITTE BROCK, ADAM DONALD FARMER, ANTHONY ROBERT HOBSON, S. MARK SCOTT, Aalborg, Denmark, Aarhus, Denmark, London, United Kingdom

Background: Up to 75% of type 1 diabetes mellitus (T1DM) patients with autonomic neuropathy experience gastrointestinal (GI) symptoms. The wire-less motility capsule (WMC) measures pH, temperature and pressure and based on anatomical landmarks we characterized the regional GI pH profile.

Aim: To compare the regional GI pH profile in T1DM patients and healthy. Furthermore, in patients to investigate the association between regional GI pH profile and clinical relevant parameters.

Methods: GI pH profiles from 48 T1DM patients with confirmed neuropa-thy (mean 50 years, SD 9.3) and 41 healthy participants (mean 49 years, SD 12.85) were included. Gastric, small bowel, large bowel and pre-expulsion mean pH values were obtained. pH changes across the antro-duodenal pas-sage and ileo-caecal junction was recorded. The association between the GI pH profile and 1) disease duration, 2) gastrointestinal cardinal symptom index (GCSI) assessed with PAGI-SYM and 3) interval between successive R-R in the electrocardiogram were tested (autonomic neuropathy).

Results: The gastric (p=0.001) and the large bowel (p=0.002) milieu were more acidic in T1DM patients in comparison to healthy. In contrast the small bowel (p=0.050) milieu was more alkalic. No difference in pH was seen for the pre-expulsion segment or the antro-duodenal change. However, the ileo-caecal change (p=0.000) was significantly higher in T1DM patients than healthy. Associations with disease duration was not found for any of the segments. Associations with GCSI were found for the large bowel pH (r=0.3911, p=0.0079) and the pre-expulsion pH (r=0.4382, p=0.0033). Asso-ciation with RR were found for the large bowel (r=-0.3029, p=0.0457).

Conclusion: Clinical associations were shown between segmental pH and GCSI and R-R interval, showing important impact on nutrient metabolism and orally drugs, directly influencing permeability, function and absorption across the gastrointestinal wall.

Supported By: Novo Nordisk A/S; Empowering Industry and Research, Northern Jutland; Innovation Fund Denmark; Individuals, Disease and Society, Denmark (10-092786); Aalborg University (to C.B.); Danish Diabetes Academy (to A.D.F.); University Hospitals of North Midlands

Respiratory gas analysis showed a significant increase in oxygen uptake and a significant decrease in respiratory quotient of IF group. In the PCR analysis, expressions of genes responsible for fat oxidation and thermogenesis (ACO, HSL and UCP1 et al.) were significantly increased in the harvested tissues (the skeletal muscle, white and brown adipose tissues). After ad-libitum feeding for 4 weeks subsequent to IF periods, BW in IF group was signifi-cantly lower than ad-libitum feeding group. At the time-point, the glucose tolerance, respiratory gas and expression of genes maintained the similar changes observed just after 4 weeks of the IF regimen.

Conclusion: The 72-hours fasting IF regimen resulted in a suppression of BW after HFD administration, in addition to a decrease in the blood glucose level.

1970‑PWestern Diet Modulates Intestinal Function: Beneficial Effects of CurcuminRYAN WALLACE, PAUL J. YANNIE, JING WANG, SIDDHARTHA S. GHOSH, SHOBHA GHOSH, Richmond, VA

Western diet (WD) induces the development of metabolic syndrome and type 2 diabetes. Strong association between circulating lipopolysaccha-ride (LPS) and metabolic diseases has shifted the focus from WD-induced changes in gut microbiota per se to release of gut bacteria-derived LPS into circulation as the possible mechanism for the chronic inflammatory state underlying the development of these diseases. We have earlier demon-strated WD-induced increase in plasma LPS as well as development of glu-cose intolerance and attenuation of these effects by oral curcumin. To delin-eate the mechanisms underlying disruption of intestinal barrier function (IBF) central to the translocation of LPS, we examined the direct effects of WD on intestinal morphology/function and its inflammatory status. LDLR-/- mice were fed chow or WD±Curcumin (by oral gavage) for 12 weeks. WD feeding led to disruption of the mucin layer that prevents direct contact between gut bacteria and intestinal epithelial cells (Panel A, arrows). WD also significantly increased the infiltration of macrophages into the intes-tinal epithelium (Panel B, left) and their polarization towards a Ly6C-Hi or pro-inflammatory M1 phenotype (Panel B, right) indicating increased intes-tinal inflammation. These effects of WD were significantly attenuated by curcumin. This study not only establishes the direct effects of WD on IBF but also confirms the protective role of curcumin.

Figures.

Supported By: American Diabetes Association (1-16-IBS-105 to S.G.)

A521


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



(CC) has restricted such studies to simple carbohydrates (SC). The aim of this study was to employ a novel tracer approach to estimate PPGM of CC and compare it with SC.

The method exploits the natural abundance of [13C]polysaccharide in food grains combined with the iv infusion of [6,6-2H2]- and [6-3H]-glucose to recre-ate the triple tracer protocol conditions already used to assess PPGM of SC.

Sixteen healthy subjects (9M, age 33±2 y, BMI 23±1 kg/m2 - mean±SE) received, in random order, either SC (labeled with [13C]glucose) or mixed meals containing [13C]grains. All meals had 50g glucose and similar macronu-trients. Plasma glucose (G) and insulin (I) were measured, while meal glucose rates of appearance (Rameal) and endogenous glucose production (EGP) were calculated. Insulin sensitivity (SI) was also estimated using the Oral Glucose Minimal Model.

Results are reported in Figure 1: all AUC0-120 and SI are significantly differ-ent in SC vs. CC with no difference in AUC0-360. If confirmed in type 1 diabe-tes, these observations would have considerable implications on prandial insulin dosing.

Supported By: National Institutes of Health (DK085516, DK029953, DK094331)

1976‑PAdvanced Glycation End Products N‑epsilon‑(Carboxymethyl)‑lysine and Pentosidine Promote Breast Cancer Cell Growth and Stemness Characteristics via Activation of SIRT6/Akt/FoxXO3A AxisCHEN YUAN CHIU, DAR REN CHEN, SHING HWA LIU, Changhua, Taiwan, Taipei, Taiwan

Recent epidemiological studies have been suggested that breast cancer (BC) and diabetes mellitus (DM) show a higher prevalence rate and risk of mortality in the same patient population. Etiology of DM and its complica-tions is not only hyperglycemia but also advanced glycation end products (AGEs) accumulation. However, the role of AGEs and the detailed mechanism of AGEs in promoting BC progression still remain unclear. Here, we investi-gated the tumorigenic potential of major AGEs, Nε-(carboxymethyl) lysine (CML) and pentosidine (PT), in MCF-7 human BC cells. Upon exposure to CML and PT (0-25 μM) for 48 hours, CML and PT both significantly promoted cell

1973‑PA New Meal Plan for DiabetesELSAMMA CHACKO, ELINA SCHWARTZ, PHYLLIS AWRUCH, Middletown, CT

Aim: To test the efficacy of a new low-carb, balanced, personalized meal plan on weight, waist circumference and HbA1c in people with diabetes and prediabetes under free-living conditions. This was an observational study.

Methods: Twenty-three adults with type 2 diabetes or prediabetes, received half-day training on a personalized, low-carb meal plan which included one big breakfast, small lunch and supper along with 2-3 snacks. Carb intake was individualized using ADA and AACE guidance: ppg of <180 mg/dL for the big meal (preferably breakfast) and <140 mg/dL for the small meals. The subjects were also told not to eat during the three hours prior to bed time. They were told not to change their general activity level. (In the next phase of the study subjects will exercise starting 30 min post the big meal). Reminders were through monthly meetings, and by phone, FAX or e-mail.

Results: Of the 23 people trained, 11 (48%) adhered to the meal plan for 3 months. The subjects included 1 man and 10 women, age 47-69, BMI 27-39. Six had prediabetes and 5 had type 2 diabetes. Four took no diabetes medi-cations, one type 2 patient was on insulin and the rest took oral agents for diabetes. Average weight reduction was 6 lbs (range +2 to -22). HbA1c came down by 0.5% (+0.2 to -1.66). Fasting glucose decreased by 44 mg/dL (+12 to -151). Waist circumference decreased by 0.47 inches, (+2” to -3.5”). No hypoglycemia or other adverse events intervened. All 11 subjects noted that eating close to bedtime raised fasting glucose, they were eating healthier meals and were satisfied by the meal plan: they reported no excessive hun-ger. All 11 subjects held full time jobs and only two could designate break-fast as the exercise meal. Four subjects chose lunch and 5 had supper for the biggest meal of the day. The subjects felt that weight reduction was proportional to decreased carbohydrate consumption.

Conclusion: A low-carb, balanced meal plan with one big meal and 2 small meals along with 2-3 snacks improved satiety, weight, waist circumference, fasting glucose and HbA1c without precipitating hypoglycemia.

1974‑PDeletion of Serotonin Receptor 2A Prevents Insulin Resistance by Increasing Energy ExpenditureABUDUKADIER ABULIZI, MICHAEL J. JURCZAK, MAX C. PETERSEN, JOAO-PAULO G. CAMPOREZ, VARMAN T. SAMUEL, GERALD I. SHULMAN, New Haven, CT, Pittsburgh, PA

Circulating serotonin (5-HT) regulates energy balance and has been reported to be increased in high fat diet (HFD)-fed rodents and diabetic humans. In this study, we examined the effects of serotonin receptor 2A (5-HT2AR) deletion on energy expenditure (EE) and whole body glucose metabolism using 5-HT2AR-/- mice. After four weeks of a high fat diet (HFD), whole-body energy expenditure was significantly increased in 5-HT2AR-

/- mice compared to wild type (WT) controls. Hyperinsulinemic-euglycemic clamp studies in HFD-fed mice revealed protection from HFD-induced whole-body insulin resistance in 5-HT2AR-/- mice (glucose infusion rate: 27.6 ± 4.9 vs. 16.6 ± 2.3 mg/(kg-min); P<0.05). Improvements in whole-body insulin sen-sitivity in HFD-fed 5-HT2AR-/- mice were accounted for both by improved suppression of endogenous glucose production (53.5±8.5 vs. 84.7±10.1%, P<0.05) and improved insulin-stimulated peripheral glucose uptake (21.8±1.8 vs. 32.7±3.7 mg/(kg-min), P=0.01). Furthermore, 5-HT2AR-/- displayed sig-nificantly decreased liver triglycerides (45% P<0.01), diacylglycerol con-tent (25% P<0.05), and PKCε activation (40% P<0.05), but unchanged liver ceramide content compared to WT controls. Plasma FGF-21 levels were also increased by (25% P<0.05) in 5-HT2AR-/- mice, suggesting a possible mecha-nism for the increase in energy expenditure. Taken together these data dem-onstrate that deletion of 5-HT2AR results in increased whole body energy expenditure, which could be attributed at least in part to increased plasma FGF-21 concentrations, leading to protection from HFD-induced nonalcoholic fatty liver disease and insulin resistance.

Conclusion: 5-HT2AR inhibition is a potential novel therapeutic target for reversing insulin resistance and type 2 diabetes.

1975‑PComplex‑Carb Triple‑Tracer Meal: Postprandial Glucose Metabo‑lism vs. Simple CarbMICHELE SCHIAVON, MAI PERSSON, CHIARA DALLA MAN, LING HINSHAW, MICHAEL SLAMA, RICKEY E. CARTER, CLAUDIO COBELLI, RITA BASU, ANANDA BASU, Padova, Italy, Rochester, MN

Postprandial glucose metabolism (PPGM) has been widely studied by iso-tope dilution method, but the difficulty of labelling complex carbohydrates

A522


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


INTEGRATED PHYSIOLOGY—MUSCLE

1978‑PThe Effect of Wasting and Stunting during Severe Acute Malnutri‑tion in Infancy on Insulin Sensitivity and Insulin Clearance in Adult LifeDEBBIE S. THOMPSON, PATRICE M. FRANCIS- EMMANUEL, ALAN T. BARNETT, CLIVE OSMOND, MARK A. HANSON, CHRISTOPHER D. BYRNE, PETER D. GLUCK-MAN, TERRENCE E. FORRESTER, MICHAEL S. BOYNE, Kingston, Jamaica, South-ampton, United Kingdom, Auckland, New Zealand, Mona, Jamaica

Objective: Adults who had non-edematous severe acute malnutrition (SAM) during infancy (also called marasmus) have worse glucose tolerance and beta-cell function than survivors of edematous SAM (i.e., kwashiorkor). We hypothesized that wasting and/or stunting in SAM is associated with lower insulin sensitivity and insulin clearance (MCR) in adulthood.

Methods: In this observational study, we recruited 40 nondiabetic adults who had SAM (20 marasmus and 20 kwashiorkor survivors) and 13 commu-nity controls who never experienced SAM. We performed 150-minute hyper-insulinaemic, euglycaemic clamps to estimate insulin sensitivity (M-values) and MCR. We also measured serum adiponectin, anthropometry and body composition. Data on wasting (weight-for-height) and stunting (height-for-age) were abstracted from the hospital records of the SAM survivors.

Results: The mean age (± SD) was 27.2 ± 8.1 years, BMI was 23.6 ± 5.0 kg/m2 and 45% were male. The groups were similar in age, weight, BMI, fat-free mass and fat mass. M-values among the marasmus, kwashiorkor and con-trols were similar (9.1 ± 3.2; 8.7 ± 4.6; and 6.9 ± 2.5 mg.kg-1.min-1 respectively; P = 0.3). MCR was also similar among the groups. The marasmus survivors had lower weight-for-height z-scores (-3.1 ± 0.7 vs. -2.2 ± 0.7; P <0.01) and height-for-age z-scores (-4.5 ± 1.3 vs. -3.3 ± 1.5; P = 0.02) than kwashiorkor survivors. Neither weight-for-height nor height-for-age was correlated with M-value, MCR or adiponectin (P-values > 0.4). These associations were not changed by adjusting for body composition, or the presence of edema.

Conclusion: Wasting and stunting during infancy are not associated with insulin sensitivity and insulin clearance in this group of lean young adult survivors of SAM. These data are consistent that glucose intolerance in mal-nutrition survivors is due to beta-cell dysfunction.

Supported By: New Zealand Health Research Council


Moderated Poster Discussion: Integrated Physiology—Muscle (Posters: 1979-P to 1984-P), see page 19.

& 1979‑PLow FGF2 in Males with Hypogonadotropic Hypogonadism and Dia‑betes: Increase after Testosterone ReplacementHUSAM GHANIM, SANDEEP DHINDSA, MANAV BATRA, KELLY GREEN, NITESH D. KUHADIYA, ANTOINE MAKDISSI, AJAY CHAUDHURI, PARESH DANDONA, Buffalo, NY, St. Louis, MO

Basic Fibroblast growth factor (FGF2) is an important stimulatory modu-lator of satellite cells in the skeletal muscle which have a cardinal role in muscle growth and repair. We hypothesized that the expression of FGF2 and its receptor (FGFR2) in the skeletal muscle of patients with hypogo-nadotropic hypogonadism (HH) and type 2 diabetes (T2DM) is reduced and that testosterone replacement therapy (TRT) results in the restoration of FGF2 expression. Twenty-two men with HH and T2DM were compared with 20 eugonadal men with T2DM at baseline. From the HH patients, 12 were treated with testosterone 200mg every 2 weeks injected intramuscularly for 24 weeks. Quadriceps muscle biopsies were obtained before and after eug-lycemic hyperinsulinemic clamps (EHC) prior to and after TRT. The expression of FGF2 and FGFR2 in skeletal muscle of HH patients were significantly lower than that in eugonadal patients by 57% and 39%, respectively (p<0.05). Fol-lowing 24 weeks of TRT, the expression of FGF2, but not FGFR2, increased significantly by 134±45% and was comparable to those in eugonadal patients. While the infusion of insulin during EHC in HH patients raised the expression of FGF2 significantly (by 142±37%) to levels comparable to those in eugonadal patients, there was no significant increase of FGF2 expres-sion in eugonadal patients after EHC. Insulin infusion during EHC increased FGFR2 expression by 53±19% in eugonadal and by 86±26% in HH patients with no effect of testosterone treatment. Plasma FGF2 concentrations were similar in both groups at baseline but increased significantly (by 37±15%) fol-lowing TRT. These data show for the first time that testosterone is a major modulator of FGF2 expression and its plasma levels and that insulin also has an acute potent stimulatory effect on FGF2 and FGFR2. Our previous work

viability (p<0.05; Fig. 1A). Increased formation of cell clones by CML (2.8- fold, p<0.05,) and PT (2.4-fold, p<0.05) (Fig. 1B) was associated with enhanced expressions of BC stemness markers (ALDH1A1, CD44, Nanog), leading to increased cell growth. As expected, protein expressions of BC stemness markers were exhibited a significant increase under the treatment of 10 and 25 μM CML and PT (p<0.05) in MCF-7 cells while exposure to CML and PT resulted in the activation of SIRT6/Akt/FoxO3A axis (p<0.05) (Fig. 1C).

In conclusion, in MCF-7 cells, CML and PT trigger expressions of stemness markers in response to cell growth via activation of SIRT6/Akt/FoxO3A axis.

Supported By: Taiwan Ministry of Science and Technology

1977‑PThe Effects of the Common Food Preservative Propionic Acid on Postprandial Metabolism and Body WeightAMIR TIROSH, EDIZ S. CALAY, GUROL TUNCMAN, KATHRYN C. CLAIBORN, KOSEI EGUCHI, MORAN RATHAUS, IDIT RON, RAJESH GARG, GÖKHAN S. HOTAMISLIGIL, Boston, MA, Tel-Hashomer, Israel

Propioic acid (PA) is a potent mold inhibitor, widely used as a preservative by the food industry. Of note, PA was previously demonstrated to acutely increase blood glucose in mammals, attributed to increased gluconeogenic substrate flux. Here we report that in mice, acute exposure to PA results in glycogenolygsis and a rapid increase in glucose release. This effect is mediated by an increase in circulating levels of both glucagon and fatty-acid binding protein 4 (FABP4 or aP2), two fasting hormones known to increase hepatic glucose production. FABP4 deficient mice as well as mice lacking the liver glucagon receptor were protected from PA effects. While PA did not increase glucagon and FABP4 secretion directly, it activated the sym-pathetic nervous system leading to increased glucagon and FABP4 release. Pharmacological inhibition of either norepinephrine release or action signifi-cantly attenuated the PA-induced increase in glucagon and FABP4, prevent-ing the hyperglycemic response. In a randomized, double-blinded, placebo-controlled cross-over study conducted on healthy human volunteers, a mixed meal test containing PA resulted in increased post-prandial glucagon, Fabp4 and norepinephrine levels as compared to a placebo-supplemented meal, associated with compensatory hyperinsulinemia and mild hyperglycemia. Chronic exposure of mice to PA at a dose equivalent to that used for food preservation resulted in increased adiposity and insulin resistance. This effect was prevented in FABP4-deficient mice or by treatment with FABP4 neutralizing antibodies.

In conclusion, the PA activates catecholamine-mediated increase in insu-lin counter-regulatory signals, leading to an inappropriate increase in post-prandial hepatic glucose release and compensatory hyperinsulinemia, which overtime may lead to weight gain and insulin resistance. These findings war-rant careful evaluation of the metabolic consequences of chronic exposure of humans to PA-containing processed foods.

Supported By: Harvard Medical School (to A.T.); Brigham Research Institute (CVDM-BRI to A.T.); Israeli Ministry of Health Research (to A.T.)

A523


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



& 1982‑PAthletes Are Resistant to Lipid‑Induced Insulin Resistance by Maintaining Higher Rates of Muscle Glucose Uptake and Glycogen SynthesisESTHER PHIELIX, SOFIYA GANCHEVA, PAUL BOGOVATZ, ALESSANDRA BIERWA-GEN, MATTHIJS HESSELINK, PATRICK SCHRAUWEN, MICHAEL RODEN, Maas-tricht, Netherlands, Düsseldorf, Germany

Introduction: Skeletal muscle insulin resistance is due to impaired muscle glucose transport and glycogen synthesis both under conditions of type 2 diabetes and augmented lipid availability. Presently, it is unknown whether chronically exercise-trained persons are prevented from lipid-induced insulin resistance and if so what could be the underlying mechanisms.

Methods: Nine sedentary and 8 trained participants were matched for age (23±1 and 27±1 years, p=n.s.). By design, in comparison with sedentary, trained participants had higher VO2max peak values (33±2 vs. 56±1 ml/kg/min, p<0.05) and were more insulin sensitive (insulin-stimulated glucose dis-posal (DRd): 59±4 vs. 44±5 μmol/kg/min, p<0.05). Participants underwent two 6h-hyperinsulinemic-isoglycemic clamp test days with either the infu-sion of saline or intralipid, performed in a 3.0 T whole body scanner with par-allel in vivo glycogen and glucose-6-phosphate measurements in the vastus lateralis muscle using 13C/31P magnetic resonance spectroscopy.

Results: Insulin sensitivity remained higher in trained vs. sedentary upon lipid infusion (DRd: 26±3 vs. 17±3 μmol/kg/min, p<0.05). Net glyco-gen synthesis rate decreased only with 27% in trained vs. a 56% decrease in sedentary participants upon lipid infusion (p<0.05). In accordance, glu-cose-6-phosphate did not decrease in trained upon 6 h intralipid infusion compared to saline (0.23±0.02 vs. 0.28±0.02 mmol/l, p=n.s.). In sedentary glucose-6-phosphate concentrations were markedly lower upon intralipid vs. saline infusion (0.17±0.02 vs. 0.37±0.07 mmol/l, p<0.05).

Conclusion: In contrast to sedentary persons, chronically trained individu-als maintain higher rates of muscle glucose transport/phosphorylation and net glycogen synthesis, during increased lipid availability, both of which account for their higher insulin sensitivity.

& 1983‑PHigh‑Fat Diet‑Induced Insulin Resistance Is Not Associated with Impaired Mitochondrial Respiration or Increased H2O2 Emission in Mouse Skeletal MuscleHARRISON D. STIERWALT, SEAN A. NEWSOM, MATTHEW M. ROBINSON, Cor-vallis, OR

Decreased skeletal muscle mitochondrial respiration and increased H2O2 emission are implicated, but not always demonstrated, in the development of insulin resistance. Whether treatment of insulin resistance can reverse potential mitochondrial detriments is not well known. The purpose of this study was to investigate substrate-specific mitochondrial respiration and H2O2 emission following induction of insulin resistance by high fat diet (HFD) and restoration of insulin sensitivity with pioglitazone (PIO). C57/BL6J mice consumed either 60% HFD or low fat diet (LFD) for 4 weeks, then for 8 more weeks the diets were either enriched in PIO (HFD+PIO, n=14; LFD+PIO, n=12) or continued as control (HFD+CON, n=10; LFD+CON, n=8). Intra-peritoneal insulin tolerance testing revealed HFD+CON had attenuated responses of 42% and 46% compared to LFD+CON (P = 0.04) and HFD+PIO (P < 0.01), respectively, indicating a lower insulin sensitivity with HFD that was improved with PIO treatment. Mitochondria were isolated from quadriceps muscle and measured by high-resolution respirometry using glutamate-malate-succinate (GMS) or palmitate (PALM) as substrate. H2O2 emission was measured during GMS respiration. Maximal PALM respiration was 45% higher in HFD vs. LFD mice (P < 0.01), with no effect of PIO within diet groups (P = 0.75). By contrast, neither GMS respiration (P = 0.66) nor H2O2 emission (P = 0.44) were influenced by HFD or PIO treatment.

In summary, the decrease in insulin sensitivity with HFD was not asso-ciated with any measured detriment in mitochondrial respiration or H2O2 emission, and insulin-sensitizing treatment did not produce any alterations in these measures. These observations demonstrate a dissociation between mitochondrial respiration and restoration of insulin sensitivity. However, it does appear that 12 weeks of HFD is sufficient to increase maximal PALM respiration in mice.


has shown that testosterone is an insulin sensitizer and thus it would appear that the two hormones work in concert to ensure appropriate growth and repair of the skeletal muscle.

Supported By: National Institute of Diabetes and Digestive and Kidney Diseases

& 1980‑PBlocking Nitric Oxide Impairs Cellular Insulin Sensitivity in Mus‑cle, without Affecting Insulin Access to the InterstitiumCATHRYN M. KOLKA, REBECCA L. PASZKIEWICZ, ISAAC ASARE BEDIAKO, RICHARD N. BERGMAN, Los Angeles, CA

Nitric Oxide (NO) causes vasodilation of blood vessels in skeletal muscle, and is thought to aid in the delivery of insulin to the muscle tissue intersti-tium. We have previously shown that insulin’s concentration in interstitial fluid is essential for insulin-mediated glucose uptake in that tissue. Previous studies have shown that L-NAME, which inhibits NO synthase, can reduce insulin-mediated glucose uptake. In this study we investigated whether this impairment was due to a decreased insulin delivery to the muscle intersti-tium. Anesthetized dogs were exposed to basal insulin levels for 180 min followed by hyperinsulinemia (1.2mU/min/kg); glucose was infused at a vari-able rate to maintain euglycemia. L-NAME was infused at 50μg/min/kg for an hour prior to hyperinsulinemia, and continued throughout the experiment. Infusion of L-NAME reduced the glucose infusion rate compared to control animals (11.2+1.1mg/min/kg in CON (n=8), 8.3+1.1 in L-NAME (n=4)), indicat-ing insulin resistance. At steady state, arterial insulin was 73.0+6.1mU/L in CON, compared to 94.6+6.2 in L-NAME, while lymph (interstitial) insulin con-centrations were 51.8+5.1 and 68.7+6.2mU/L respectively. The similar ratio of lymph:plasma at steady state suggested no L-NAME induced impairment in insulin access to the interstitial space. Tissue insulin sensitivity (SItissue = Dleg glucose uptake/(Dlymph insulin x Glucose) was markedly impaired with L-NAME (3.4+0.4 vs. 1.0+0.2mg/min/kg, P<0.01). We conclude that NO inhibition results in insulin resistance, both systemic and cellular. L-NAME infusion also seemed to increase insulin levels during the clamp, indicating a possible impairment in liver insulin clearance (MCR), and yet we detect no impairment of insulin access to the interstitium as hypothesized. Thus, our results suggest that NO is involved in cellular insulin sensitivity rather than vascular effects of insulin to promote glucose uptake.

& 1981‑PDysfunctional Muscle Microvascular and Aortic Responses to Insu‑lin in Type 1 DiabetesLINDA JAHN, FARHAD HASAN, LEE HARTLINE, ZHENQI LIU, ALVIN TAN, EUGENE BARRETT, Charlottesville, VA

In health, insulin increases glucose disposal and microvascular recruit-ment in skeletal muscle and may decrease arterial stiffness. Whether these responses to insulin are preserved in type 1 diabetes (DM1) is uncertain. We measured before and during a 2-hr, 1mU/min/kg insulin clamp: a) the glucose infusion rate (GIR) needed to maintain euglycemia; b) muscle microvascu-lar blood volume (MBV-contrast ultrasound); and c) arterial stiffness (pulse wave velocity-PWV and augmentation index-AI) in 16 control and 15 other-wise healthy DM1 adults. The GIR was less in DM1 than in controls (p<0.05), indicating metabolic insulin resistance. Insulin increased MBV in controls (47±13%) but not DM 1 (-4±22%, p<0.01, for the differences). Indeed, MBV declined with insulin in 10 of 15 DM1 subjects but only 1/16 controls. GIR cor-related positively with changes in MBV (r= 0.49, p<0.01). PWV was not dif-ferent between groups at baseline but after insulin infusion PWV was faster (6.2±0.5 vs. 5.1±0.4 m/sec, p<0.02) in DM1, suggesting enhanced aortic stiff-ness. AI was not different between groups before or after insulin infusion. While AI and PWV are both used as indices of arterial stiffness the correla-tion between these measures was relatively weak in DM1 and controls both before (r=0.34) and after (r=0.32) insulin. In controls and DM1 subjects VO2max correlated strongly with GIR and inversely with AI but not PWV.

We conclude that: 1) muscle microvasculature is resistant to the vasodila-tory action of insulin in DM1, indeed a vasoconstrictor response is common; 2) microvascular insulin resistance correlates with metabolic insulin resis-tance; 3) in DM1 insulin increases aortic stiffness (PWV) acutely, suggesting paradoxical vasoconstriction; 4) arterial stiffness measured by PWV and AI assess distinctly different vascular properties.


A524


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



1986‑PKnockdown of Estrogen Receptor‑alpha in Human Myotubes from Healthy or Obese‑Insulin Resistant Women Decreases Mitochon‑drial Respiration and ATP Production RatesMELISSA MAE R. INIGO, KEITH G. JONES, TIMOTHY D. HEDEN, KATSUHIKO FUNAI, ESPEN E. SPANGENBURG, Greenville, NC

The development of the metabolic syndrome in women is often associ-ated with a reduction in skeletal muscle estrogen receptor-alpha (ERa) func-tion. However, the underlying mechanisms that explain the role of ERa in skeletal muscle metabolism remain poorly understood. Previous research in mouse models suggests that ERa expression influences regulatory aspects of glucose and lipid metabolism. However, it is unclear if these results trans-late to human skeletal muscle.

Purpose: The purpose of this study was to determine if ERa expression in human skeletal muscle is necessary to maintain mitochondrial function.

Methods: Primary human skeletal muscle cells were isolated from healthy or obese-insulin resistant (OIR) young adult women. Myoblasts were trans-duced with AV-driven scrambled-shRNA (Scrmbl) or ERa-shRNA (ERaKD) and then differentiated for 5 days into mature myotubes. ERa expression was quantified by real-time PCR, and mitochondrial respiration was assessed using the Seahorse XF Analyzer.

Results: ERa mRNA expression was significantly lower by 87% in ERaKD myotubes when compared to the Scrmbl condition. In myotubes from healthy subjects, ATP production rate was significantly lower in ERaKD group com-pared to the Scrmbl myotubes. In myotubes from OIR subjects, basal oxygen consumption rate and ATP production rate were significantly lower in ERaKD myotubes compared to the Scrmbl condition. No differences in uncoupled oxygen consumption were found between control and ERaKD myotubes from either healthy or obese groups.

Conclusions: The data suggest that ERa is critical in maintaining mito-chondrial basal oxygen consumption rate and ATP production rate in human skeletal muscle.

Supported By: American Diabetes Association (1-15-BS-170 to E.E.S.)

1987‑PLack of O‑GlcNAcylation Enhances Exercise‑Dependent Glucose Utilization through Amp Kinase Activation in Skeletal MuscleKOICHIRO MURATA, KATSUTARO MORINO, SHOGO IDA, NATSUKO OHASHI, HIROTAKA IWASAKI, MENGISTU LEMECHA SHUKARE, OSAMU SEKINE, SHINJI KUME, SHI YOUNG PARK, CHEOL SOO CHOI, SATOSHI UGI, HIROSHI MAEGAWA, Otsu, Japan, Incheon, Republic of Korea

O-GlcNAcylation is a post-translational modification that is characterized by the addition of N-acetylglucosamine to various proteins by O-GlcNAc transferase (Ogt). This modification is thought to be associated with glu-cose metabolism, because it serves as “a nutrient sensor” that can regulate diverse cellular processes in response to nutritional status. However, its role in skeletal muscle has not been fully elucidated. In this study, we created skeletal muscle-specific Ogt knockout mice (Ogt-MKO) and analyzed their glucose metabolism. During intraperitoneal glucose tolerance test, blood glucose levels were not different between Ogt-MKO and control Ogt-flox mice, whereas plasma insulin levels in Ogt-MKO were slightly lower than control mice. These results suggested that Ogt-MKO had a better insulin sensitivity. However, there was no significant difference in either insulin-dependent blood glucose lowering or Akt phosphorylation (Ser 473 and Thr 308) in skeletal muscle between the 2 groups. We thus hypothesized that lack of O-GlcNAcylation might enhance exercise-dependent glucose utiliza-tion in skeletal muscle. During 20 minutes single bout of exercise, Ogt-MKO mice showed lower levels of blood glucose and plasma insulin, which was accompanied by enhanced phosphorylation of ACC (Ser 79), a substrate of AMP kinase (AMPK). Furthermore, intraperitoneal injection of AICAR, an AMPK activator, resulted in a marked decrease in blood glucose levels in Ogt-MKO as compared with control group. Finally, Ogt knockdown by siRNA in C2C12 myoblasts significantly increased phosphorylation of AMPK (Thr 172), leading to higher glucose oxidation determined with Seahorse Extra-cellular Flux analysis.

In conclusion, loss of O-GlcNAcylation facilitates glucose utilization via AMPK activation in skeletal muscle. The inhibition of O-GlcNAcylation in skeletal muscle may have antidiabetic effect through enhancing glucose utilization during exercise.


& 1984‑PTestosterone Induces AMP Kinase‑α ExpressionSANDEEP DHINDSA, HUSAM GHANIM, MANAV BATRA, JEANNE HEJNA, KELLY GREEN, NITESH D. KUHADIYA, ANTOINE MAKDISSI, AJAY CHAUDHURI, PARESH DANDONA, St. Louis, MO, Buffalo, NY

AMP kinase-α induces phosphorylation of AKT kinase, thus activating it. This, in turn, results in the transport of GLUT4 to the membrane to increase glucose transport. This mechanism, though independent of insulin action, can amplify insulin signal transduction since insulin action also involves AKT kinase and GLUT4. AMP kinase mediates the action of exercise to enhance glucose transport and the action of adrenergic stimulation and metformin treatment. Following our recent observation that type 2 diabetes (T2DM) with hypogonadotropic hypogonadism (HH) is associated with increased insulin resistance by 36% when compared with eugonadal T2DM and that this reverses with testosterone replacement, we hypothesized that this phenomenon may be associated with an increase in cellular AMP kinase. Twenty-two men with HH and T2DM were compared with 20 eugonadal men with T2DM at baseline. From the HH patients, 12 were treated with testosterone 200mg every 2 weeks injected intramuscularly for 24 weeks. Hyperinsulinemic, euglycemic clamps (HEC) were carried out prior to and after testosterone replacement and fat (abdomen) and muscle (quadriceps) biopsies were carried out prior to and after HEC procedure on each occasion. The expression of AMP kinaseα was significantly lower by 37% and 29%, in adipose tissue and muscle, respectively, from HH patients compared to eugonadal patients and did not respond to hyperinsulinemia (clamp) in either tissue in HH patients at baseline. Following testosterone replacement, the expression of AMP kinase-α did not alter in the fasting state but increased markedly by 41±9% and 46±11% in adipose tissue and muscle, respectively, after the infusion of insulin and glucose during the clamp procedure. We conclude that testosterone modulates insulin and glucose induced expres-sion of AMP kinaseα. This may contribute to the improved insulin sensitivity and glucose homeostasis after testosterone replacement.


1985‑PFebuxostat Improves Skeletal Muscle Insulin Resistance via Upregulating Skeletal Muscle PGC‑1α Expression in High‑Fat Diet‑Fed Male Wistar RatsCHIHIRO MORIYA, HIROAKI SATOH, HIROTAKA WATADA, Tokyo, Japan

Hyperuricemia is closely associated with various metabolic disorders such as diabetes, hypertension, dyslipidemia, and cardiovascular diseases. Xanthine oxidoreductase (XOR) is a key enzyme known to catalyze purines to uric acid. Febuxostat is an orally-active, potent, non-purine, selective XOR inhibitor. However, the effect of febuxostat on glucose and insulin metab-olism has not been fully elucidated. In current study, we investigated the effect of febuxostat on insulin sensitivity in male Wistar rats, whereby insu-lin sensitivity was measured directly using the hyperinsulinemic-euglycemic glucose clamp studies (at 25 mU/kg/min insulin infusion rate) after an 8 hour fast. Male Wistar rats were fed normal chow diet (NCD), or 60% high fat diet (HFD) containing with either febuxostat (~4 mg/kg/day) or not, for 4 weeks. In the NCD fed rats, during the clamp studies, the glucose infusion rate (GIR), the clamp hepatic glucose output (cHGO) and insulin-stimulated glucose disposal rate (IS-GDR) were no significant changes between two groups. On the other hand, in the HFD fed rats, the GIR and IS-GDR were sig-nificantly increased by 12% and 17%, respectively, in febuxostat group com-pared to in the HFD fed control group. But cHGO was no significant change between two groups. Consistent with the clamp data, the insulin-stimulated phosphorylation of Akt and AMPK were significantly increased by 90% and 53%, respectively, in skeletal muscle of HFD fed febuxostat treated HFD fed rats. Furthermore, peroxisome proliferator-activated receptor-γ coactivator (PGC)-1α expression in skeletal muscle, which is a key regulator of mitochon-drial content and function, was significantly increased by 2 folds in HFD fed febuxostat treated rats compared to the HFD fed control rats, as assayed by real-time qRT-PCR.

In conclusion, our findings demonstrated that febuxostat had beneficial effects on skeletal muscle insulin sensitivity in an insulin resistant state.

A525


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



ment that predisposes individuals with low birth weight to type 2 diabetes, and it highlights HDAC7 as one of these candidate genes.

Supported By: Rigshospitalet; Danish Council for Independent Research; Euro-pean Foundation for the Study of Diabetes; Aase and Ejnar Danielsens Foundation; Novo Nordisk Foundation

1990‑PLong‑Term Rates of Skeletal Muscle Mitochondrial Protein Syn‑thesis Are Increased with High‑Fat Feeding but Not Changed with Insulin Sensitizing Treatment in MiceSARAH E. EHRLICHER, KARYN L. HAMILTON, BENJAMIN F. MILLER, SEAN A. NEWSOM, MATTHEW M. ROBINSON, Corvallis, OR, Fort Collins, CO

Skeletal muscle mitochondrial protein synthesis and protein breakdown are regulated by insulin and may be impaired with insulin resistance. Short-term periods (e.g., <24 hours) that are commonly used to measure protein synthesis or degradation may not adequately capture the effects of long-term insulin resistance. Deuterium oxide (D2O) labeling allows for long-term measurement of protein synthesis (PS) over days to weeks and integrates fasting and feeding periods. The purpose of this study was to measure long-term PS and markers of autophagy in skeletal muscle following changes in insulin sensitivity. C57/BL6J mice consumed either a low fat diet (LFD) or high fat diet (HFD) for 4 weeks, then diets were either enriched in pio-glitazone (PIO) or not (CON) for 8 weeks to form groups of LFD+CON (n=8), HFD+CON (n=10), LFD+PIO (n=12) and HFD+PIO (n=13). HFD+CON had higher fasting plasma insulin than LFD+CON while PIO lowered plasma insulin in both HFD (~47%, P < 0.01) and LFD groups (~40%, P = 0.02), which is consis-tent with induction of insulin resistance with HFD then treatment with PIO. D2O was added to drinking water during the final 2 weeks to measure PS rates of a mitochondrial (Mito) enriched fraction of the quadriceps. Mito PS (%/day) of HFD+PIO (2.99 ± 0.35) was greater compared to LFD+CON (2.43 ± 0.21, P < 0.01) and LFD+PIO (2.55 ± 0.36, P = 0.01) but did not differ from HFD+CON (2.80 ± 0.41, P = 0.54). Protein breakdown was assessed via immu-noblotting of autophagy markers p62 and LC3 in the quadriceps. Compared to LFD, HFD mice had lower p62 content (P < 0.01) and greater LC3II/LC3I (P = 0.03) suggesting increased autophagy with HFD, and PIO treatment did not alter the response. Long-term rates of Mito PS and autophagy markers were increased in mice with insulin resistance and not changed with PIO treatment. We conclude mitochondrial protein synthesis and autophagy are not impaired with insulin resistance and instead are increased.


1991‑PGlobal Acetylome Analysis of Muscle Reveals Differentially Lysine Acetylated Sites in ObesityROCIO ZAPATA BUSTOS, JEAN FINLAYSON, PAUL LANGLAIS, ELENA A. DE FILIPPIS, LAWRENCE J. MANDARINO, Tucson, AZ, Scottsdale, AZ

Understanding molecular mechanisms regulating exercise response and their relationship with insulin resistance is incomplete. Differential acetyla-tion (Ac) of muscle proteins in insulin resistance could be relevant for exer-cise resistance. This study analyzed Ac in resting muscle from lean (L) and obese (O) subjects to identify differentially acetylated sites. Subjects (7 L and 11 O) had euglycemic clamps with vastus lateralis biopsies taken basally. Proteins were analyzed in an Orbitrap Elite Velos Pro mass spectrometer; Ac was quantified using spectral abundance factors. O subjects were insulin resistant (glucose disposal rate of 9.49±0.86 mg/kg-1·min-1 vs. 4.68±0.76 mg/kg-1·min-1, L vs. O). Proteomic analysis identified 492 lysine acetylated proteins, 378 had 1 lysine acetylated peptide and the rest had 2-17 differ-ent acetylated peptides. Nine proteins had significantly (P<0.05) different lysine Ac between L and O. Myosin-8 and SERCA 2 were acetylated at sites 32 (0.001±0.0005) and 352 (0.0017±0.0008), in the L group but were not detected in O. Other proteins with higher Ac in the L group were 14-3-3 pro-tein zeta/delta (0.186±0.018 vs. 0.112±0.022 in site 3), EIF1 (0.464±0.083 vs. 0.183±0.053 in site 18), Ran-binding protein 3 (0.571±0.170 vs. 0.136±0.097 in site 9) and histone H3.1/H3.3 (0.121 ±0.035 vs. 0.025 ±0.013 in site 15), for L vs. O groups. ADP/ATP translocase 1 had higher Ac in O (0.0014±0.0009 and 0.006±0.001 at site 272, L vs. O). Tyrosine kinase CSK was acetylated at site 420 only in O (0.697±0.138); this Ac site was not detected in L. Histone Ac relaxes chromatin and allows transcription to occur, so lower Ac in O could explain lower gene expression responses seen in obesity and insulin resistance. CSK negatively regulates the Src family tyrosine kinases and is regulated through its own (SH2) domain. The K420 Ac site found only in O is adjacent to a YXXM SH2 recognition motif. Ac in this site could restrict intra-molecular protein interactions which may interfere with regulation of Src.

Supported By: National Institutes of Health (DK066483)

1988‑PCharacteristics of Glucose Metabolism in Japanese Nondiabetic Underweight WomenYUKI SOMEYA, YOSHIFUMI TAMURA, RURIKO SUZUKI, HIDEYOSHI KAGA, DAISUKE SUGIMOTO, SATOSHI KADOWAKI, KAGEUMI TAKENO, SAORI KAKEHI, TAKASHI FUNAYAMA, YASUHIKO FURUKAWA, RYUZO KAWAMORI, HIROTAKA WATADA, Tokyo, Japan

Asian people easily developed to type 2 diabetes (T2DM) even with nor-mal BMI (<25 kg/m2). Interestingly, as well as overweight, underweight (UW) (BMI<18.5kg/m2) Japanese women have ~2 times higher risk for T2DM compared with normal-weight (NW). Although the prevalence of UW in Japanese young women reached to ~20%, the mechanisms of increased risk of T2DM in UW women are unknown.

To investigate the feature of glucose metabolisms in UW Japanese women, we recruited nondiabetic UW (BMI: 16.0-18.5kg/m2) and NW (BMI: 18.5-23.0 kg/m2) in young (20-29 years old; UW, n=31; NW, n=13) and post-menopausal women (50-65 years old; UW, n=30; NW, n=10). All participants underwent OGTT and measurements of intramyocellular lipid (IMCL) and body composition by 1H-magnetic resonance spectroscopy and dual-energy X-ray absorptiometry, respectively.

In young group, the frequency of IGT was comparable between NW women (15%; 2 in 13) and UW women (13%; 4 in 31). On the other hand, in postmeno-pausal group, the frequency of IGT was higher in UW women (37%; 11 in 30), than in NW women (0%; 0 in 10). Compared with young UW women, post-menopausal UW women showed higher HbA1c and AUC-glucose during OGTT and lower insulinogenic index and AUC-insulin during OGTT, while body com-position and IMCL levels were comparable between the groups. Comparison between IGT and NGT subjects in postmenopausal UW women revealed that IGT subjects have lower lean body mass (IGT; 31.8±3.6 kg, NGT; 34.5±3.3 kg, p=0.04) and higher IMCL (IGT; 3.1±1.3 AU, NGT; 2.2±0.8 AU, p=0.02) with no difference of insulinogenic index and AUC-insulin. In addition, the 2 h glucose level during OGTT was significantly correlated to lean body mass (r=-0.51, p<0.01) and IMCL (r=0.40, p=0.03) in UW postmenopausal women.

These data suggest that impaired insulin secretion with aging may exac-erbate glucose tolerance in underweight postmenopausal women. In addi-tion, decreased muscle mass and IMCL accumulation may further increase the risk of IGT in underweight postmenopausal women.

Supported By: Japan Ministry of Education, Culture, Sports, Science and Tech-nology

1989‑PEpigenome‑ and Transcriptome‑Wide Changes In Muscle Progeni‑tor Cells Isolated from Men with Low Birth Weight Associate with Impaired In Vitro Muscle Differentiation and Glucose UtilizationCHRISTA BROHOLM, RASMUS RIBEL-MADSEN, ANDERS H. OLSSON, JULIANE AHLERS, NINNA S. HANSEN, MAREN SCHRÖLKAMP, LINE HJORT, LINN M. GILL-BERG, ALEXANDER PERFILYEV, PETR VOLKOV, CHARLOTTE LING, SINE W. JØR-GENSEN, BRYNJULF MORTENSEN, JANNE HINGST, JØRGEN F.P. WOJTASZE-WSKI, CAMILLA SCHEELE, CHARLOTTE BRØNS, BENTE K. PEDERSEN, ALLAN VAAG, Copenhagen, Denmark, Malmö, Sweden, Gentofte, Denmark

Low birth weight at term due to impaired intrauterine nutrient supply is a risk factor for type 2 diabetes. Metabolic adaptations which can explain this increased risk have been described in several organs including skeletal muscle, where insulin-stimulated glucose uptake is reduced. We recently characterized muscle satellite cells isolated from young men with low birth weight and showed an impaired development into muscle fibers. Therefore, we aimed to study the epigenome- and transcriptome-wide adaptations that underlie the functional differences in satellite cells from the low birth weight men. Primary cultures of myoblasts were established and differen-tiated into myotubes, and RNA and DNA was harvested before and after differentiation. Genome-wide microarray-based comparisons between low- and normal birth weight men of DNA methylation and gene expression identified differences which were more pronounced in myoblasts than myo-tubes. Fifteen cytosine-p-guanine dinucleotides were differentially methyl-ated in myoblasts from low compared to normal birth weight men (P<1.5×10-

6, q<0.05). Furthermore, an approximate 20% reduction of gene expression was found for the tyrosine kinase gene FYN (P=8.8×10-8, q=0.007) and the histone deacetylase gene HDAC7 (P=1.1×10-5, q=0.04) in low birth weight myoblasts. Concomitant minor DNA methylation changes occurred in these genes (P=0.02, q=0.5). We characterized the genes further by siRNA silenc-ing experiments including analyses of cellular glucose uptake. Silencing of HDAC7, but not FYN, led to impaired myotube formation and reduced insulin-stimulated flux of glucose. The study suggests that specific DNA methylation and transcriptional changes associate with the impaired muscle develop-

A526


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



Figure.

Supported By: National Basic Research Program of China (81520108014)

1994‑PR3h Domain Containing‑Like Has Pivotal Roles in Skeletal Muscle Development and RegenerationKENICHI SAKAMOTO, MINORU TAKEMOTO, YASURO FURUICHI, MEGUMI TAKA-HASHI, YOSHIHIRO AKIMOTO, MASASHI YAMAMOTO, TAKAHIRO ISHIKAWA, TAKAHIKO SHIMIZU, YASUKO MANABE, NOBUHARU FUJII, YOSHIRO MAEZAWA, CHRISTER BETSHOLTZ, KOUTARO YOKOTE, Chiba, Japan, Tokyo, Japan, Uppsala, Sweden

Background and Aim: It was reported that the muscle loss due to dis-ability of muscle to regenerate was accelerated in elderly patient with diabetes, leading to insulin resistance and frailty. However the mechanism of muscle regeneration is poorly understood. In this scenario, satellite cells have essential roles for muscle development and regeneration. In this study, we have found a novel gene, R3hdml and analyzed functionally in skeletal muscle.

Methods: The expression pattern of R3hdml in skeletal muscles, iso-lated satellite cells, and C2C12 cells were analyzed by reverse transcription polymerase chain reaction and Western blotting, and in situ hybridization. Cardiotoxin (CTX) was injected into the muscle to induce muscle regenera-tion. R3hdml knockout (KO) mice were also created and the resulting muscle phenotypes were analyzed.

Results: The expression of R3hdml was increased along with differen-tiation of C2C12 cells and isolated satellite cells. Myotubule formation was attenuated by 26.1% due to the lack of R3hdml in C2C12 cells. The muscles from 20-week-old R3hdml KO mice were significantly lighter than littermate controls. The expression of Igf-1 and phosphorylation of Akt within the mus-cle were decreased in R3hdml KO mice by 27.2% and 49.2%, respectively. The expression of Ccnd1 (CyclinD1) and Ki67 were decreased by 39.0% and 72.5% respectively, while the expression of Cdkn1a (p21) was increased by 76.0% in the muscles of R3hdml KO mice. Further, the expression of Ki67 was decreased by 17.1% in isolated satellite cells dissected from R3hdml KO mice. The expression of R3hdml was increased in MyoD positive cells after CTX injection, indicating that R3hdml was expressed in activating satellite cells which undergoing proliferation in vivo. The recovery of hand grip after CTX injection was slower in R3hdml KO mice compared with controls.

Conclusion: R3hdml, a novel skeletal muscle satellite cell expressed gene, is important for skeletal muscle differentiation and regeneration.

1995‑PParkin‑Mediated Mitophagy Is Essential for Maintaining Cardiac Function in Diabetic MiceSATORU KOBAYASHI, FENGYI ZHAO, YUAN HUANG, AMANDA KAMINARIS, ERIC LAM, TAMAYO KOBAYASHI, YOUHUA ZHANG, QIANGRONG LIANG, Old Westbury, NY

Oxidative stress and mitochondrial dysfunction are critical to diabetic heart damage. However, antioxidant therapies have failed to reduce heart failure in clinical trials, underscoring the need to develop new therapeutic strategies. A healthy pool of mitochondria is maintained through a number of quality control mechanisms including mitophagy that degrades dysfunc-tional mitochondria. In the present study, we investigated the role of car-diac mitophagy in streptozotocin-induced diabetic mice. We showed that mitophagy flux was reduced in the diabetic heart as indicated by a novel mitophagy reporter, which was accompanied by increased mitochondrial fragmentation and impaired cardiac function. Similarly, high glucose inhib-

1992‑PImplication of Circulating Meteorin‑Like (Metrnl) Protein Level with Type 2 DiabetesHYE SOO CHUNG, HYE JIN YOO, SEI HYUN BAIK, SIN GON KIM, NAN HEE KIM, JI A. SEO, KYUNG MOOK CHOI, Seoul, Republic of Korea, Gyeonggi, Republic of Korea, Ansan, Republic of Korea

Background: Meteorin-like (Metrnl) protein is a novel adipomyokine induced by exercise and cold in muscle and adipose tissue. Previous studies have shown that Metrnl improved glucose tolerance by enhancing insulin sensitivity and suppressed chronic inflammation in mice. However, the asso-ciation between serum Metrnl levels and diabetes risk in human remains unclear. We examined the difference of circulating Metrnl levels between subjects with and without type 2 diabetes.

Methods: Age matched subjects (400 diabetes and 400 nondiabetes) from the Korean Sarcopenic Obesity Study (KSOS) were included. Serum Metrnl concentrations were measured with the ELISA kits. Basic anthropometric parameters, fasting plasma glucose, marker for kidney function and serum lipid profile were also measured.

Results: The serum Metrnl levels were higher in subjects with diabetes than without diabetes (diabetes: 1219.9 (1020.6,1535.6), nondiabetes: 1131.2 (993.1,1313.6) pg/ml (median (interquartile range), P<0.001). After adjust-ing for age and sex, Metrnl levels were negatively correlated with SBP (P=0.011), DBP (P<0.001), Total cholesterol (P<0.001), low-density lipoprotein (LDL)- cholesterol (P=0.003), Triglyceride (P<0.001), hemoglobin (P<0.001), glucose (P=0.009), and estimated glomerular filtration rates (eGFR) (P<0.001) and it was positively correlated with BUN (P=0.002), and creatinine (P<0.001) in total group. In a multiple logistic regression analysis, the odds ratio for diabetes risk was 2.787 (95% confidence interval [CI] = 1.579-4.919) in the highest tertile of Metrnl compared to the lowest after adjusting for potential confounding factors.

Conclusions: This cross-sectional study demonstrated for the first time that circulating Metrnl level is elevated in the subjects with diabetes com-pared to control, and is an independent risk factor associated with diabetes.

1993‑PEvaluation of the Alteration of Slow‑ and Fast‑Twitch Muscles to Type 2 Diabetes in Monkeys by MRIYUSHU CHEN, WEN ZENG, JIE ZHENG, FABAO GAO, Chengdu, China, St. Louis, MO

Aim: To quantify the alteration of slow and fast skeletal muscles to type 2 diabetes mellitus (T2DM) in rhesus monkey by a non-contrast MR perfusion and oximetry techniques.

Methods: 7 T2DM (HbA1c = 7.75 ± 2.95%) and 4 normal monkeys (14±3y) were tested by original MRI techniques for skeletal muscle blood flow (SMBF) and oxygen extraction fraction (SMOEF) with an air-cuff protocol. 3 ROIs were placed on the triceps surae-, tibialis anterior- and peroneus lon-gus muscle for SMBF. And a ROI covered the whole calf muscle for SMOEF. 2 monkeys were sacrificed for HE and ATPase staining.

Results: The altered SMBF in each cuff-phases between normal and T2DM have no differences. But for T2DM, from inflation to hyperemic (P<0.01), and from hyperemic to deflation (P<0.01) are significant differences in triceps surae muscle, but no differences in other muscles. These results are confirmed by HE staining. For SMOEF, from inflation to deflation for the normal, from resting to inflation and from inflation to deflation for the T2DM are significant differences. ATPase staining confirmed soleus leg muscle was predominantly the type 1 (slow-) fiber while the others were mainly the type 2 (fast-) fiber.

Conclusions: MRI microcirculation mapping techniques can quantify the impaired perfusion and oxygenation in skeletal muscles, suggesting the diverse adaptation of slow- and fast-twitch skeletal muscles to T2DM.

A527


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


INTEGRATED PHYSIOLOGY—OTHER HORMONES

whereas various cardiolipins, ceramides, phosphatidic acids and phosphati-dylethanolamines were negatively correlated with VO2max in both lean and obese individuals at baseline. After weight loss, there were positive correla-tions of VO2max with prostaglandins, dipeptides, nucleotides and ceramides, and a negative correlation of VO2max with various dipeptides and amino acid derivatives. MtDNA appeared to mediate the effects of VO2max on metabolites both before and after weight loss. The effects of VO2max were age-independent and there was no effect of VO2max on age-related changes in metabolite levels. The results suggest higher VO2max is associated with increased SKM fatty acid oxidation (increased acylcarnitines) and reduced proteolysis (reduced amino acids, alterations in dipeptides) at both baseline and after weight loss, independent of age and partly mediated by higher mtDNA count number.

Supported By: National Institutes of Health; A. Alfred Taubman Medical Research Institute

1998‑PSkeletal Muscle Metabolism Is Altered with Age and NFκB Sup‑pressionJOSEPH M. VALENTINE, SANGEETA GHOSH, NICOLAS MUSI, San Antonio, TX

Alterations to muscle mitochondrial function have been proposed as a mechanism for diabetes and aging-associated insulin resistance. Similarly, the “sterile” low-grade inflammatory state observed in diabetes and aging is thought to play a role in these pathologies. A key mediator of this inflam-matory response is the transcription factor NFκB. To investigate how altera-tions in inflammation during aging can affect mitochondrial function, we utilized mice with muscle-specific overexpression of a super repressor of NFκB (MISR). We hypothesized that MISR mice would be protected against aging-related changes to mitochondria. RNA sequencing revealed that genes involved in mitochondrial function (AMPK, PGC1, SIRT, ETC subunits) where differentially expressed between WT and MISR mice throughout aging. These alterations did not result in muscle oxygen consumption rate differences between 3-6 month old WT and MISR mice measured by high-resolution respirometry. However, O2 consumption in response to both com-plex I and II substrates was significantly lower in 12-18 month old MISR mice compared to age matched controls by ~20%. Interestingly, 12-18 month old WT mice had significantly higher O2 consumption rates in response to CI and CII substrates compared to young animals of either genotype by ~40%. ATP production and citrate synthase activity were not altered. The changes in respiration with age and suppression of canonical NFκB signaling were also accompanied by differences in H2O2 production. Specifically, H2O2 production in response to CI, pyruvate dehydrogenase, and fat oxidation substrates was elevated in 12-18 month old WT mice compared to young mice by ~30%, 15%, and 250% respectively. 12-18 month old MISR mice maintained H2O2 production rates comparable to those of young mice. Our current findings suggest that suppression of canonical NFκB signaling alters expression of genes involved in mitochondrial function resulting in reduced mitochondrial ROS production and O2 consumption during aging.

Supported By: American Diabetes Association (7-13-GSK-01 to N.M.)


Moderated Poster Discussion: Integrated Physiology—Other Hor-mones (Posters: 1999-P to 2004-P), see page 21.

& 1999‑PNo Evidence of Increase in Calcitonin Concentrations or Develop‑ment of C‑Cell Malignancy in Response to Liraglutide in the LEADER TrialLASZLO HEGEDÜS, STEVEN SHERMAN, R. MICHAEL TUTTLE, BERNT JOHAN VON SCHOLTEN, SØREN RASMUSSEN, JULIE DERVING KARSBØL, GILBERT H. DANIELS, LEADER TRIAL STEERING COMMITTEE AND INVESTIGATORS, Odense, Denmark, Houston, TX, New York, NY, Søborg, Denmark, Boston, MA

To date, there is no evidence that liraglutide stimulates calcitonin (CT) release in humans. This secondary analysis of the LEADER trial (NCT01179048) examines the long-term CT changes in patients exposed to liraglutide vs. placebo.

Patients (n=9340) with type 2 diabetes and high risk for cardiovascular (CV) events were randomized 1:1 to liraglutide or placebo, and followed for up to 5 years. The study investigated a composite CV outcome. We analysed: the change of CT levels over time; CT outliers; and thyroid and C-cell neoplasms.

ited mitophagy but increased mitochondrial fragmentation in cultured car-diomyocytes. Overexpression of the E3 ubiquitin ligase Parkin increased mitophagy flux and diminished high glucose toxicity; while Parkin knockdown had the opposite effects. In addition, manipulating the expression levels of the fission factor Drp1 affected not only mitochondrial fragmentation but also mitophagy flux and cardiomyocyte injury. In vivo, enhancing mitophagy in diabetic heart by Parkin overexpression improved cardiac function and attenuated oxidative stress and apoptosis. In contrast, inactivation of Parkin gene increased diabetic cardiac injury. Together, these results suggest that mitophagy plays an important role in maintaining mitochondrial quality and cardiac homeostasis in diabetes. Our cell culture results also demonstrate the interplay between mitochondrial fission and mitophagy, suggesting that the coupling status of the two processes may affect hyperglycemic cardiac injury given the ability of fission process to segregate injured mitochondria and send them for degradation through mitophagy. This question warrants further investigation.


1996‑PCapillary Dropout and Heterogeneous Perfusion during Hyperinsu‑linemia in Insulin ResistancePENN M. MCCLATCHEY, IAN M. WILLIAMS, DAVID H. WASSERMAN, JANE E.B. REUSCH, Aurora, CO, Nashville, TN, Denver, CO

Objective: Evidence suggests that insulin resistance (IR) involves reduced insulin and glucose delivery to skeletal muscle. To test the hypothesis that altered muscle perfusion contributes to IR, we developed a software tech-nique and applied it to intravital microscopy data obtained during hyperin-sulinemia to quantify skeletal muscle capillary perfusion in a mouse model of IR.

Methods: Cell tracking software was developed to quantify capillary den-sity, capillary diameter, and blood flow velocity from intravital microscopy videos from gastrocnemius muscle after injection of insulin (4 U/kg) and glu-cose (0.5 g/kg). Mean flow velocity, coefficient of variance of flow velocity (std/mean), proportion of non-flowing capillaries, capillary density, and mean capillary diameter were compared between chow-fed (CH, n=6) and high fat-fed (HF, n=4) mice.

Results: Gastrocnemius anatomical capillary density was reduced from 924/mm2 CH to 463/mm2 HF (p=0.004). The proportion of non-flowing capil-laries was increased from 5% CH to 35% HF (p=0.003), contributing to a reduction in perfused capillary density from 882/mm2 CH to 290/mm2 HF (p=0.001). The coefficient of variance of flow velocity (a metric of perfusion heterogeneity) was increased from 0.648 to 1.298 (p<0.001). Applying Fick’s law of diffusion, the observed decreases in capillary density with HF cor-respond to an increase in capillary-interstitial insulin gradient of up to 4x (using anatomical capillary density) or 9x (using perfused capillary density).

Conclusions: HF diet causes significant impairment of capillary perfusion during hyperinsulinemia, including capillary dropout and heterogeneous per-fusion. These results provide a plausible mechanism for impaired insulin and glucose delivery to skeletal muscle in IR. Our findings echo previous stud-ies of resting skeletal muscle perfusion in the Obese Zucker Rat (Frisbee et al, AJP 2011) and the GK rat (Padilla et al, 2006), suggesting that perfusion defects contribute to IR.

Supported By: U.S. Department of Veterans Affairs; University of Colorado

1997‑PEffect of Intrinsic Oxidative Capacity (VO2max) on Mitochondrial DNA (mtDNA) and Metabolites in Skeletal Muscle (SKM)CHANISA THONUSIN, CHARLES R. EVANS, HEIDI B. IGLAYREGER, AMY E. ROTH-BERG, GEORGE MICHAILIDIS, CHARLES F. BURANT, Ann Arbor, MI, Gainesville, FL

People with higher VO2max have a decreased risk of metabolic diseases and age-related mortality. Our previous study showed that high VO2max slowed age-related changes in human plasma metabolite levels, i.e., delayed metabolic aging. To identify whether the effect of VO2max is medi-ated in part by mtDNA in SKM, we assessed VO2max as well as SKM mtDNA content and metabolite levels in a group of lean (n = 15) as well as obese individuals before (n = 99) and after (n = 41) a 17.2 +/- 1.2% diet-induced weight loss. MtDNA count number was positively correlated with VO2max but was not significant after weight loss. After adjustment for age, sex, race, BMI, HOMA and diabetes status, targeted metabolomics showed that acyl-carnitines were positively correlated with VO2max at baseline and became more pronounced after weight loss. In contrast, SKM free amino acids were negatively correlated with VO2max which diminished after weight loss. Untargeted metabolomics revealed that phosphatidylinositols and phospha-tidylserines and oxodecanoic acid were positively correlated with VO2max,

A528


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



& 2001‑PFABP4 as a Potential Regulator of Neonatal Glucose HomeostasisIDIT RON, REUT KASSIF LERNER, MORAN RATHAUS, TSIPORA STRAUSS, KEREN OFIR, ITAI PESSACH, AMIR TIROSH, Tel-Hashomer, Israel

Fatty acid-binding protein 4 (FABP4 or aP2) was recently identified as an adipokine with key roles in systemic metabolism and in promoting hepatic gluconeogenesis (GNG) by regulating the expression of its rate-limiting enzyme, phosphoenolpyruvate carboxykinase (PEPCK). During normal preg-nancy, fetal GNG is absent and is evident only soon after birth with a rapid increase in the expression of PEPCK. Thus, FABP4 may play an important role in neonatal glucose homeostasis by regulating the GNG ‘switch-on’ immediately after birth. We therefore studied the dynamics in FABP4 lev-els in maternal, fetal and neonatal circulations. Serum samples were col-lected from 47 pregnant women at term immediately before delivery (51% with gestational diabetes, GDM), from the umbilical artery and vein after birth and from the newborns within the first few hours of life. As previously described, GDM was associated with significantly elevated levels of mater-nal FABP4 as compared to normoglycemic women (24.7±15.9 vs. 15.2±7.6 ng/mL, p=0.029). FABP4 level in the fetal circulation was significantly higher than that observed in the nondiabetic maternal circulation (23.3±15.3 and 23.6±15.2 ng/mL for umbilical artery and vein, respectively). After birth, neonatal FABP4 levels further increased by ~3-fold over fetal levels reach-ing a value of 65.2±37.5 ng/mL (p=0.001). Neonatal FABP4 levels inversely correlated with blood glucose, with levels as high as 94.8±59.8 ng/mL recorded among neonates who developed hypoglycemia (glucose <40 mg/dL). Increased FABP4 levels in hypoglycemic newborns were observed even in the presence of elevated insulin levels, known to suppress FABP4 secre-tion. Taken together, the significant increase in fetal FABP4 levels immedi-ately before delivery, which continue to increase during the first hours of life coincides with the activation of GNG in the newborn. The rapid and robust increase in circulating FABP4 during hypoglycemia suggest that this novel adipokine may act as an insulin counter-regulatory hormone.

Supported By: Israel Diabetes Association

& 2002‑PRegulation of Biphasic Exocytosis of Glucagon‑Like Peptide‑1 by the SNARE Protein Syntaxin1aSARAH E. WHEELER, YASAMAN NAHAEI, FIONA M. GRIBBLE, FRANK REIMANN, HERBERT GAISANO, PATRICIA L. BRUBAKER, Toronto, ON, Canada, Cambridge, United Kingdom

The incretin glucagon-like peptide-1 (GLP-1) facilitates metabolic homeo-stasis through enhancement of glucose-dependent insulin secretion. To develop new approaches for the treatment of type 2 diabetes, the capacity to enhance endogenous GLP-1 secretion from the intestinal L cell is currently being explored. Although secretagogues that stimulate GLP-1 secretion have been identified, the mechanism of exocytosis remains unknown. We previously used intestinal epithelial-specific inducible syntaxin1a knock-out (IE-syn1a KO) mice to show that loss of syn1a in the mouse intestine reduces oral glucose-stimulated GLP-1 secretion in association with defi-cient glucose-stimulated insulin release and glucose intolerance. We there-fore hypothesized that loss of syn1a impairs L cell exocytosis. Secretion assays performed on adult mouse ileal cell (AMIC) cultures generated from IE-syn1a KO mice demonstrated no difference in basal GLP-1 secretion as compared to control animals. However cultures from IE-syn1a KO mice dis-played a 2.6-fold reduction in forskolin-stimulated GLP-1 secretion, to 37% of the response found in controls (p<0.001). We thus crossed IE-syn1a KO mice with proglucagon-Venus mice to permit identification of the L cell for exocytotic analysis. An oral glucose tolerance test revealed that, like the IE-syn1a KO mice, these mice demonstrated impaired glucose tolerance (p<0.05). 2-Photon microscopy revealed biphasic L cell exocytosis, with a 1st peak at 1-6 min and a 2nd peak at 7-12 min after stimulation with forskolin. Compound granule fusion accounted for ~75% of exocytotic events under both basal and stimulated conditions. Furthermore, at the single L cell level, 1st phase forskolin-induced exocytosis was reduced to basal (p<0.05) and 2nd phase exocytosis was abolished (p<0.05) by syn1a knockout, although basal release was not affected. This finding identifies syn1a as a positive regulator of stimulated GLP-1 secretion and, hence, insulin release following a meal.

At 36 months, patients randomized to liraglutide showed no difference in mean CT concentrations vs. patients randomized to placebo in male (esti-mated treatment ratio [ETR]: 1.03, 95% confidence interval [CI]: 1.00; 1.06; p=0.068) and female subgroups (ETR: 1.00, 95% CI: 0.97; 1.02; p=0.671) (Fig-ure). In liraglutide vs. placebo groups, a similar proportion of male (24.6 vs. 23.0%) and female (5.4 vs. 4.5%) patients had a post-baseline CT concen-tration above the upper normal limit during the trial. No episodes of C-cell hyperplasia or medullary thyroid carcinoma were reported in patients in the liraglutide group.

There was no indication of a difference in CT concentrations between treatments and no C-cell malignancies occurred in the liraglutide group.

Figure. Calcitonin Concentrations Over 5 Years.

Supported By: Novo Nordisk A/S

& 2000‑PBeta‑Cell GLP‑1R Signaling Contributes to Improvements in Islet Morphology after Vertical Sleeve Gastrectomy in MiceDARLINE GARIBAY, JON LOU, SEON A. LEE, JAMES FICORILLI, AMY L. COX, DODSON MICHAEL, KYLE W. SLOOP, BETHANY P. CUMMINGS, Ithaca, NY, Indianapolis, IN

Vertical sleeve gastrectomy (VSG) produces high rates of type 2 diabetes remission; however, the mechanisms responsible for this are incompletely defined. Postprandial glucagon-like peptide-1 (GLP-1) secretion increases after VSG in humans and rodent models. We recently reported that the β-cell GLP-1 receptor (GLP-1 R) contributes to improved glucose tolerance and islet function after VSG, using a β-cell specific tamoxifen-inducible GLP-1 R knock-out mouse model. Previous work demonstrates that GLP-1 exerts beneficial effects on islet morphology; however, the role of the β-cell GLP-1 R in the effect of bariatric surgery to improve islet morphology is unknown. There-fore, we tested the hypothesis that β-cell GLP-1 R contributes to improved islet morphology after VSG. At 8 wks of age, β-cell specific GLP-1 Rβ-cell+/+

(WT) and GLP-1 Rβ-cell-/- (KO) male mice were placed on a high fat diet (HFD) for 6 wks and then switched to HFD supplemented with 400 mg tamoxifen/kg diet for the rest of the study. Mice underwent sham (S WT and S KO) or VSG (VSG WT and VSG KO) surgery at 16 wks of age and were fed ad libi-tum post-operatively (n=4 per group). Mice were euthanized at 6 wks after surgery. Paraffin embedded pancreas sections were fluorescently stained and quantified for insulin and glucagon. Consistent with previous reports in rodent models of bariatric surgery, β-cell area per islet was decreased in VSG WT compared with S WT (S WT = 5648 ± 190, VSG WT = 3578 ± 501 μm2; P<0.05 S-WT vs. VSG WT). However, β-cell area per islet did not differ between KO groups (S KO = 4965 ± 1194, VSG KO = 5895 ± 1927 μm2). Surprisingly, α-cell area per islet was increased in VSG WT compared with S WT (S WT = 860 ± 87, VSG WT = 1250 ± 136 μm2; P<0.05 S WT vs. VSG WT). This effect was lost in VSG KO vs. S KO (S KO = 851 ± 134, VSG KO = 934 ± 187 μm2). This study provides exciting new evidence that VSG increases islet glucagon content and is the first to show that β-cell GLP-1 R signaling contributes to improvements in islet morphology after VSG.

A529


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



2005‑PMetabolic Switch by O‑GlcNAcylation Is Essential for Cold‑Induced Thermogenesis in Brown Adipose TissueNATSUKO OHASHI, KATSUTARO MORINO, SHOGO IDA, OSAMU SEKINE, MEN-GISTU LEMECHA, SHINJI KUME, SHE YOUNG PARK, CHEOL SOO CHOI, SATOSHI UGI, HIROSHI MAEGAWA, Otsu, Japan, Incheon, Republic of Korea

Brown adipose tissue (BAT) plays significant roles in lipid and glucose metabolisms. During cold exposure, increased glucose and fatty acid oxida-tion appears to maintain core temperature in BAT. O-GlcNAcylation is char-acterized by the addition of N-acetylglucosamine, an end product of a branch of glycolysis pathway, to various proteins by O-GlcNAc transferase (Ogt). However, little is known about the role of O-GlcNAcylation in BAT. Dele-tion of Ogt in BAT (Ogt-BKO) led to hypertrophy and lipid accumulation, and resulted in severe cold intolerance with decreased Ucp1 expression. Intra-peritoneal glucose tolerance tests (IPGTTs) during cold exposure resulted in decreased glucose levels compared with room temperature (RT) in both genotypes. Although IPGTTs revealed no significant differences at RT, Ogt-BKO mice displayed significantly lower glucose levels compared with con-trol mice during cold exposure. In addition, the hypothermia was rescued by oral glucose injection, not by oral fat load. This effect in Ogt-BAT was mitigated following normal diet consumption but not following consumption of a ketogenic diet lacking carbohydrates, suggesting impaired diet-induced thermogenesis, particularly by fat.

In conclusion, O-GlcNAcylation is essential for cold-induced thermogen-esis and fat oxidation in BAT, and glucose flux into BAT may be a signal to maintain BAT physiological responses.

Figure.

Supported By: Japan Society for the Promotion of Science; National Research Foundation

2006‑PMethylglyoxal Leads to Osteoporosis through Activation of Osteo‑clastDICKY K.M. LEE, CHING CHING TAM, KEVIN K. YUE, Hong Kong, China

Purpose of the Study: Diabetes mellitus (DM) is characterized by chronic hyperglycemia and diabetic complications. Methylglyoxal (MG) is a reactive metabolite of glucose and one of the most reactive advanced glycation end-product precursors in which abnormal accumulation is found in the serum of diabetic patients. In clinical studies, diabetic patients have higher risk to suf-fer from osteoporosis. Osteoclast, which regulates the resorption of bone, is severely affected by MG. Hence the effect of MG leading to subsequent osteoporosis was investigated.

Methods: SD rats were treated with MG (50mM, 10mL/kg) for 8 weeks. Proximal end of tibia were collected for analysis. The bone mineral density (BMD) and mRNA expression of osteoclastic biomarkers were measured using micro-CT and RT-PCR respectively.

Summary of the Results: Using micro-CT scanning, compared with control group (383.2 ± 17.7 mg HA/ccm) lower trabecular BMD was observed in MG group (318.1 ± 10.9 mg HA/ccm). Change of trabecular architecture was also observed after MG treatment. In addition, using RT-PCR it was found that there were increased mRNA expressions of osteoclast biomarkers CTSK (Cathepsin K) (1.51 ± 0.15 fold), OSCAR (Osteoclast-associated receptor)

& 2003‑PGrowth Hormone Regulation of G0S2 and FSP27: Mechanism for Growth Hormone‑Mediated LipolysisQUYEN V. LUONG, RITA SHARMA, VISHVA SHARMA, MITCHELL HARBERSON, JOHN KOPCHICK, VISHWAJEET PURI, KEVIN Y. LEE, Athens, OH

Growth Hormone (GH) has long been known to stimulate lipolysis; how-ever, the molecular mechanisms behind these effects remain unexplored. In the present study, we demonstrate that both fasting and GH administration acutely induce lipolysis in human patients. This effect is secondary to the reduced expression of two lipid droplet proteins that are negative regula-tors of lipolysis - G(0)/G(1) switch gene 2 (G0S2) and Fat Specific Protein 27 (FSP27), also known as Cell Death Inducing DFFA like Effector C (CIDEC)- at both the mRNA and protein levels. These effects are mimicked in vivo, as transgenic over-expression of GH in mice leads to reduction of G0S2 and FSP27 expression. Utilizing primary and 3T3-L1 adipocytes, we demonstrate that GH modulation of G0S2 and FSP27 expression is mediated through two intersecting molecular pathways. The dominant GH regulated pathway is dependent on MEK/ERK phosphorylation of peroxisome proliferator-activated receptor gamma (PPARG). This phosphorylation leads to nuclear exclusion of PPARG, resulting in reduced transcription of G0S2 and FSP27 and increased lipolysis. MEK inhibitor, U0126, and PPARG activator, Rosi-glitazone, completely abolish GH-mediated lipolysis and reduction of FSP27 and G0S2 expression. Furthermore, GH treatment leads to the activation of a second counter-regulatory pathway in which STAT5 and PPARG directly interact in a GH-dependent manner. Utilizing specific inhibitors of STAT5 and luciferase reporter assays, we show that the interaction between STAT5 and PPARG specifically activates transcription of the FSP27 gene. Finally, we demonstrate that over-expression of FSP27 is sufficient to repress GH-medi-ated lipolysis in cultured adipocytes. Taken together, these data in human subjects, mice, and cellular models decipher the molecular mechanism by which GH acutely and tightly controls lipolysis in adipose tissue.

2004‑P

WITHDRAWN

A530


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



H4 in various organs in the Sirt3-KO mice, which modifies gene expressions, should lead to the alteration in the GLP-1 level.

2009‑PNext Generation of FGF‑21 Analogs: Engineered Short‑ and Long‑Acting FGF‑21 Variants with Improved In Vivo Potency, Stability, and Biopharmaceutical PropertiesMALGORZATA GONCIARZ, DAVID DRIVER, CRAIG D. DICKINSON, AMY FORD, TERESA A. MOREHEAD, JAMES D. DUNBAR, HANA E. BAKER, LIBBEY S. O’FARRELL, ANTHONY T. MURPHY, RYAN J. HANSEN, ANDREW C. ADAMS, TAMER COSKUN, RYAN DARLING, Indianapolis, IN

FGF-21 has emerged as a promising therapeutic target for treatment of diabetes, dyslipidemia and NASH. Lilly has previously evaluated FGF-21 v1 (LY2405319) both preclinically and in clinical setting. Preclinically, FGF-21 v1 showed similar effects to pharmacological effects of native FGF-21. In man, however FGF-21 v1 didn’t demonstrate statistically significant glucose lowering as observed in preclinical models of diabetes. We hypothesized that more potent FGF-21 analogs and/or longer exposure may be required to assess full range of FGF-21 effects in patients with established diabetes. In this report, we describe next generation of FGF-21 analogs with improved potency, pharmaceutical stability, and reduced proteolytic degradation in vivo. We have engineered a once daily FGF-21 v2 (LY3025876), and FGF-21 Long-Acting (LA; LY3053102) with extended time-action enabling once weekly dosing. FGF-21 v2 is an unconjugated FGF-21 analog, while FGF-21 LA is composed of human IgG4 Fc domain recombinantly fused to the N-ter-minus of FGF-21 analog. The potency of FGF-21 analogs was increased by introducing following substitutions D127K, S167R and G174L that resulted in significantly reduced EC50 values in in vitro potency assays. Both FGF-21 v2 and LA demonstrated ~6-fold increase in potency in glucose lowering in ob/ob mice, and 77-fold improvement in body weight lowering compared to FGF-21 v1 in DIO mice. It is known that circulating hFGF-21 is proteolytically processed by Fibroblast Activating Protease (FAP), generating inactive form of FGF-21. We improved in vivo stability of FGF-21 analogs by incorporating G170E, and reducing proteolytic susceptibility to FAP. Additional engineering was carried out to improve physicochemical properties of FGF-21 analogs and included incorporation of a disulfide bond through A31C and G43C to improve poor physical stability of FGF-21, and mutations to reduce propen-sity to self-association and aggregation.

2010‑PTwo Apelin‑13 Peptide Analogues Show Promising Therapeutic Efficacy following Chronic Administration in Diabetic db/db MiceFINBARR P.M. O’HARTE, VADIVEL PARTHSARATHY, PETER R. FLATT, Coleraine, United Kingdom

Apelin peptide analogues have previously shown promising acute in vivo antidiabetic effects in diet induced obese diabetic mice. Here we compared the efficacy of two apelin analogues, (pGlu)apelin-13-amide and (pGlu) (Lys8GluPAL)apelin-13-amide, with exendin-4 and liraglutide following chronic administration in male diabetic db/db mice (9 week old). Five groups of db/db mice (n=8) received twice daily (09:00 and 17:00 h) i.p. injection of saline vehicle, (pGlu)apelin-13-amide, (pGlu)(Lys8GluPAL)apelin-13-amide, exendin-4(1-39) or liraglutide (25 nmol/kg) for 21 days. A control group of normal C57BL/6JOlaHsd mice were treated twice daily with saline. No significant changes in body weight or food intake were noted with apelin treatments, but exendin-4 reduced cumulative food intake (p<0.01) com-pared with saline-treated db/db mice. Apelin analogues and incretin mimet-ics showed sustained improved glycemic control (p<0.05 to p<0.001, from day 9 to 21) and enhanced insulinotropic responses vs. control db/db mice. Both (pGlu)apelin-13-amide and (pGlu)(Lys8GluPAL)apelin-13-amide, along with incretin mimetics showed improved oral and i.p. glucose tolerance compared with saline-treated db/db mice (p<0.05 to p<0.001). Apelin ana-logues significantly reduced %HbA1c by 1.5-1.6% after 21 days of treatment (p<0.05) which was similar to incretin mimetics. (pGlu)apelin-13-amide was superior to incretin mimetics lowering plasma triglycerides by 34% (p<0.05) compared to saline-treated db/db mice. Apelin peptides and liraglutide unlike exendin-4 reduced pancreatic α-cell area by 15-20%, (p<0.05 to p<0.01) and all peptide treatments improved pancreatic insulin content by 39-72% (p<0.05 to p<0.01) vs. saline-treated db/db mice. Overall longer-term administration of apelin-13 based analogues was as effective or better than incretin mimetics in db/db mice over 21 days, providing a novel therapeutic approach for counteracting diabetes.

Supported By: Invest Northern Ireland; Proof of Concept (PoC518)

(1.90 ± 0.17 fold), RANK (Receptor activator of nuclear factor kappa B) (1.34 ± 0.30 fold) and TRAP (Tartrate-resistant acid phosphatase) (2.57 ± 0.28 fold) after MG treatment, indicating activation of osteoclast. (Data expressed as Mean ± SEM).

Conclusions: MG activates osteoclast, leading to lower BMD and more porous bone architecture in proximal end of rat tibia. Activation of osteo-clast may be an important event leading to imbalance bone remodeling resulting in osteoporosis.

Supported By: Hong Kong Baptist University

2007‑PMechanisms to Elevate Endogenous Glucagon‑Like Peptide‑1 (GLP‑1) beyond Levels Achieved by Injectable GLP‑1 Analogs and Bariat‑ric SurgeryDANIEL A. BRIERE, ELLEN J. GUNN, ANA B. BUENO, M. DODSON MICHAEL, KYLE W. SLOOP, Indianapolis, IN, Blue Ash, OH, Alcobendas, Spain

Circulating levels of glucagon-like peptide-1 (GLP-1) are profoundly elevated as a result of various forms of metabolic surgery. Pharmacologi-cal blockade of the GLP-1 receptor (GLP-1R) and conditional deletion of the GLP-1R in mice has implicated elevated GLP-1 as a major factor in the resolution of type 2 diabetes mellitus (T2DM) following these surgical pro-cedures. Moreover, injection of GLP-1R agonists is effective in the treatment of T2DM. Therefore, due to the therapeutic benefit of GLP-1, we sought to identify non-invasive approaches to increase endogenous GLP-1 to levels mimicking those achieved by metabolic surgery and injectable GLP-1 analogs (~ 50 pM). We hypothesized that targeting multiple regulatory mechanisms would maximize the ability to increase endogenous GLP-1 concentrations. Overnight-fasted C57BL/6 mice were given an oral bolus of olive oil to stimu-late GLP-1 secretion, a somatostatin receptor subtype 5 (SSTR5) antagonist to block inhibition of GLP-1 release, and/or a dipeptidyl peptidase-4 (DPP-4) inhibitor to preserve active GLP-1. At 15 minutes post dose, plasma levels of active GLP-1 for vehicle, olive oil, DPP-4 inhibitor, or SSTR5 antagonist were 0.3 +/- 0.1, 5.5 +/- 0.6, 1.5 +/- 0.3, and 0.8 +/- 0.2 pM, respectively. However, combination of all three agents elevated active GLP-1 to 96.3 +/- 23.4 pM (P < 0.0001). Further experiments replacing olive oil with a selective, non-bile acid TGR5 agonist demonstrated even higher levels of GLP-1 for the com-bination of three agents (350.0 +/- 85.3 pM, P < 0.0001) with GLP-1 levels staying above 50 pM for 3 hours. These studies demonstrate that comple-mentary pathways can be manipulated to substantially increase circulating GLP-1 without invasive surgery. Further, the concentration of GLP-1 achieved by such a combinatorial mechanism is similar to the levels of GLP-1 equiva-lents achieved with injectable GLP-1R agonist therapy.

2008‑PSirt3 Regulates Glucose Metabolism in Mice through Glucagon‑Like Peptide‑1ASUKA UTO, KAZUTOSHI MIYASHITA, MASAAKI SATO, SHO ENDO, CHIKAKO FUJII, MASANORI MITSUISHI, HIROSHI ITO, Tokyo, Japan

Background: Sirtuins (Sirt1-7) are longevity genes that regulate epigenetic modifications. Among them, Sirt3 is a NAD-dependent deacetylase that is known to regulate lipid metabolism in mice. Sirt3-deficient knockout (KO) mice fed a high-fat diet have been shown to develop obesity and metabolic syndrome-like phenotype at the older age.

Objective and Methods: This study investigated the effects of Sirt3 on glucose metabolism by examining the metabolic parameters in the Sirt3-KO mice. To elucidate the regulatory mechanism of glucose level through Sirt3, we estimated the expression levels of sirtuins in various organs in wild type mice and, the histone acetylation in the Sirt3-KO mice.

Results: The KO mice fed with a standard or a high-fat diet were subjected to an oral glucose tolerance test (OGTT), together with an intraperitoneal glucose tolerance test (ipGTT). OGTT demonstrated an increase in the blood glucose level in the Sirt3-KO mice, although ipGTT did not show the increase after glucose loading; fed with either a standard or a high-fat diet. Blood glucagon-like peptide-1 (GLP-1), a representative incretin, and insulin levels before and 15 minutes after oral glucose loading were examined in the KO mice. GLP-1 and insulin levels were found to decrease in the KO mice both before and after the glucose loading. PCR analysis revealed the predomi-nated expression levels of Sirt3 in the small intestine, colon, kidney, and liver in the wild type mice. The immunostaining of acetylated histone H3 and H4 showed enhanced intensity in the glandular and stromal cells in the small intestine and colon, and in the renal tubular cells and the vascular endothelial cells in the KO mice.

Conclusion: These results suggests that Sirt3 deficiency impairs the incre-tin effect by a suppression of GLP-1. Enhanced acetylation of histone H3 and

A531


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



2013‑PAcute Effects of Combined DPP‑4 and SGLT2 Inhibition on Fasting and Postchallenge Glucagon, Insulin, and GLP‑1 LevelsJAN W. ERIKSSON, PER LUNDKVIST, MARIA J. PEREIRA, PETROS KATSOGIAN-NOS, RUSSEL ESTERLINE, ANNA MARIA LANGKILDE, EVA JOHNSSON, Uppsala, Sweden, Mölndal, Sweden

SGLT2 inhibitors(i) can increase and DPP-4i generally decrease glucagon (glg) secretion, but the mechanisms are not fully understood. In a 3-way crossover study, 15 metformin-treated T2D subjects received a single oral dose of Dapagliflozin 10mg (Dapa) ± Saxagliptin 5mg (Saxa) followed by a 5 h infusion of saline (or glucose, not reported here) and then a 2 h OGTT. During fasting (saline), glg rose by addition of Saxa compared to Dapa alone although glucose lowering was similar. Active GLP-1 (aGLP-1) increased with Saxa and was higher than with Dapa alone. Insulin (ins) did not differ significantly and glg/ins ratio rose similarly regardless of Saxa. Beta-OH-ketones were elevated by Dapa alone, and this was not affected by Saxa. During OGTT, glucose increased less with Saxa than with Dapa alone. Saxa also lowered the average glg levels, but starting from a higher level. Ins and C-peptide rose, glg/ins fell and none was affected by Saxa. Active GLP-1 was elevated during OGTT and the maximum level, but not relative response, was increased 2-fold by Saxa. In fasting T2D patients given a single dose Dapa, concomitant Saxa increased glg and aGLP-1 levels. In OGTT, Saxa reduced glg. Data indicates that incretin effects on pancreatic islets are complex during SGLT2i, since DPP-4i paradoxically increased fasting glg but had no clear effect on glucose-stimulated ins levels. (NCT02765204).

Table. Percent Change from Baseline with Dapa 10 mg ± Saxa 5 mg.Experiment Glucagon Insulin Glg/ins aGLP-1Dapa, saline -8±3 -30±2 37±6 -20±9Dapa/Saxa, saline 9±4 -3±17 32±11 102±28Difference 16±3** 27±16 -5±10 122±30**Dapa, OGTT -10±6 246±28 -62±3 412±85Dapa/Saxa, OGTT -21±4 211±19 -66±2 323±77Difference -11±4* -35±25 -4±3 -89±99Mean±SEM, % delta-AUC plasma conc; fasting (saline) or OGTT; *p<0.05. **p<0.01.

2014‑PMicrobiota in the Upper Small Intestine Alters Gut Hormone‑Dependent Fatty Acid Sensing Pathways to Influence Whole Body Glucose HomeostasisPAIGE V. BAUER, FRANK A. DUCA, HELEN J. DRANSE, AKSHITA PURI, BRITTANY A. RASMUSSEN, CATHERINE A. O’BRIEN, TONY K.T. LAM, Toronto, ON, Canada

The gut microbiota is implicated in glucose regulation; however the major-ity of work to date has focused on the distal intestinal microbiota despite the fact that the upper small intestine harbors a significant microbial com-munity. Upper small intestinal lipid sensing activates preabsorptive nega-tive feedback pathways to lower glucose production in healthy, but not high fat diet-fed conditions. However, whether specific individual fatty acids can alter whole body glucose homeostasis and whether high fat diet-induced changes in the gut microbiota alter these pathways to impair glucose regula-tion, remains unknown. We here find that upper small intestinal infusion of Intralipid, oleic acid, or linoleic acid improves glucose tolerance in healthy but not high fat diet-fed rats. This effect is associated with the ability of oleic acid to lower glucose production via a gut CCK and GLP-1 receptor-dependent pathway, while the effect of linoleic acid is independent of CCK but requires GLP-1 receptor activation. High fat diet feeding impairs both fatty acid sensing pathways in association with a decrease in Lactobacilla-ceae and an increase in Clostridiaceae and Enterobacteriaceae in the upper small intestine. Transplantation of upper small intestinal microbiota from high fat diet rats to healthy, regular chow rats abolishes fatty acid sensing, demonstrating that HFD-induced changes in the gut microbiota disrupt fatty acid sensing. Conversely, the transfer of upper small intestinal microbiota from healthy rats to high fat diet rats restores fatty acid sensing to improve glucose regulation, with a restoration in the abundance of Lactobacillaceae, Clostridiaceae and Enterobacteriaceae to that of the regular chow condition.

In summary, we here unveil a previously unappreciated glucoregulatory role for the upper small intestinal microbiota, which regulates gut hormone-dependent fatty acid sensing pathways to alter glucose regulation.

Supported By: Canadian Institutes of Health Research

2011‑PDeterminants of Glucagon‑Like Peptide‑1 Secretion and Intra‑indi‑vidual Variability in Healthy AdultsSHEETAL MALHOTRA, VIVIANA BAUMAN, ALLISON C. SYLVETSKY, JENNA ABDELHADI, JENNY BLAU, KENNETH J. WILKINS, KRISTINA ROTHER, Rockville, MD, Bethesda, MD, Washington, DC

Glucagon-like peptide-1 (GLP-1) regulates glucose metabolism by stimu-lating insulin secretion, inhibiting glucagon secretion, and slowing gastric emptying. Little is known about the reproducibility of GLP-1 responses and its determinants. The aim of our study was to examine the effects of age, sex and BMI on intra-individual variability of GLP-1 responses.

Methods: GLP-1 data from healthy volunteers (n=61, 54% women) that underwent four 2-hour oral glucose tolerance tests (OGTTs) to assess effects of non nutritive sweeteners on glucose were assessed. Blood samples were collected at -10, 0, 10, 20, 30, 60, 90, and 120 minutes and active GLP-1 was measured (by ELISA) and log transformed. Mixed-effects models were fit to assess the consistency of basal, peak, delta (peak-basal), and area under the post-OGTT curve (AUC) for Box-Cox transformed GLP-1. Intra-individual vari-ability in GLP-1 adjusted for sex was quantified by random subject-effects’ variance, and ratio of intra- to inter-individual variability was estimated overall as well as stratified by sex. Point estimates of these ratios were <1 for all, and the upper limit of the 95% confidence intervals were less than unity for all but 2 female subgroups.

Results: Mean age of the participants was 28.3±7.1 y. Basal GLP-1 was higher in men than women (6.58 ± 6.12 vs. 3.25 ± 3.42, p=0.03), but not affected by BMI (p=0.74) or age (p=0.65). There was little intra-individual variability in basal GLP-1 across repeated OGTTs relative to the inter-individual variability (ratio 0.24, 95% CI 0.15-0.37) and for AUC (ratio 0.29, 95% CI 0.18-0.44). Men had a higher peak GLP-1 (18.94 ± 11.87 vs. 13.09 ± 8.09, p=0.02), and AUC (1454.98 ± 970.32 vs. 947.90 ± 549.97, p= 0.02) than women. Compared to females, males had higher inter-individual variability in peak GLP-1 and delta GLP-1.

Conclusion: GLP-1 secretion is associated with sex, but not with BMI and shows high intra-individual reproducibility indicating tight regulation.

2012‑PDirect vs. Indirect Actions of Ghrelin on Hypothalamic NPY NeuronsHIROSHI HASHIGUCHI, VANESSA ROUTH, MARC SIMARD, YOSHIHIKO NISHIO, JOSEPH BRYAN, Kagoshima, Japan, Newark, NJ, Baltimore, MD, Seattle, WA

Objective: Assess direct vs. indirect action of ghrelin on hypothalamic NPY neurons.

Methods: Electrophysiology was used to measure ion channel activity in NPY-GFP neurons in slice preparations. Ca2+ imaging was used to monitor ghrelin activation of isolated NPY GFP-labeled neurons. Immunohistochem-istry was used to localize Trpm4, SUR1 and Kir6.2 in the hypothalamus.

Results: Acylated ghrelin depolarized the membrane potential (MP) of NPY-GFP neurons in slices. Depolarization was accompanied by a decreased input resistance (IR) in ~70% of neurons (15/22) or increased IR in the remain-der (7/22), consistent with opening or closing of ion channels, respectively. Tetrodotoxin (TTX), which blocks presynaptic action potentials, reduced both MP and IR, but ghrelin did significantly increase MP and decrease IR in TTX-treated neurons suggesting ghrelin directly opens an ion channel(s). Phar-macologic studies demonstrated the importance of the adenylate cyclase/protein kinase A and phospholipase C/IP3 pathways as activators of AMPK. Reducing [Na+]o suppressed activation suggesting a role for non-selective cation channels. SUR1 and two channel partners, Kir6.2 and Trpm4, were identified immunologically in NPY-GFP neurons in situ and the actions of SUR1 and Trpm4 modulators proved informative. Like ghrelin, a SUR1 ago-nist elevated [Ca2+]c and a SUR1 antagonist partially suppressed ghrelin action, while selective Trpm4 antagonists blocked ghrelin action on isolated neurons.

Conclusions: Consistent with recent work, ghrelin stimulates presynaptic inputs that activate NPY-GFP neurons directly in situ. Ghrelin can also directly depolarize neurons either by activating a depolarizing conductance(s) or inhibiting a hyperpolarizing conductance(s). Results with isolated NPY-GFP neurons suggest the ghrelin-activated, depolarizing current is a Na+ con-ductance with the pharmacologic properties of Trpm4/SUR1 non-selective cation channels.


A532


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



mmol/mol) and controls (n=10, BMI: 31.8±1.3 kg/m2; HbA1c: 33.9±0.9 mmol/mol) underwent two 4-hour liquid mixed meal tests with preceding single-dose administration of GRA (100 mg) or placebo, respectively. Compared to pla-cebo, GRA lowered fasting PG in patients with T2D (6.9±0.3 vs. 9.4±0.8 mM, P=0.002) and controls (5.0±0.1 vs. 5.5±0.1 mM, P<0.0001). Postprandial area under the curve (AUC) of PG was lower in patients with T2D with GRA com-pared to placebo (2,382±115 vs. 2,873±223 mM × min, P=0.02), but not in controls (1,570±65 vs. 1,494±22 mM × min, P=0.26). Incremental AUC of PG was unaffected by GRA in patients with T2D (723±87 vs. 625±66 mM × min, P=0.25) but increased in controls compared to placebo (370±66 vs. 177±29 mM × min, P=0.01). C-peptide responses (assessed by AUC) were similar for GRA compared to placebo in patients (514±42 vs. 518±56 μM × min, P=0.92) and controls (429±34 vs. 425±38 μM × min, P=0.82). Postprandial glucagon responses were more than doubled by GRA compared to placebo in patients with T2D (AUC 6,493±1,184 vs. 2,894±688 pM × min, P=0.0003) and controls (AUC 3,937±543 vs. 1,208±191 pM × min, P<0.0001). Gastric emptying was similar during the two experimental days (as assessed by the acetamino-phen absorption test).

In conclusion, LY2409021 lowers fasting PG in patients with T2D and con-trols, but does not diminish postprandial PG excursions after a mixed meal indicating that the effects of the GRA is driven mainly by effects on pre-meal PG levels.

Supported By: Novo Nordisk Foundation; Eli Lilly and Company

2018‑PAssociation of Testosterone and Vitamin D Levels with Metabolic Indices in Elderly Individuals with Impaired Fasting GlucoseKALLIOPI KOTSA, ASTERIOS BATOS, XANTHIPPI TSEKMEKIDOU, KONSTANTI-NOS KALESIS, SPYRIDON KARRAS, PANAYIOTIS TSAKLIS, KYRIAKOS KAZAKOS, PANTELIS ZEBEKAKIS, Thessaloniki, Greece

The purpose of this study is to examine the association of testosterone and vitamin D levels with metabolic parameters in elderly individuals with impaired fasting glucose (IFG).

Subjects and Methods: 161 elderly men (>65 years old) were divided into three groups: patients with diabetes mellitus (DM) (n=50), IFG (n=67) and control group (CG) (n=44). BMI, waist circumference, morning Fasting Glucose (FG), insulin, vitamin D, testosterone, HBA1c and blood lipids were measured in all participants. SPSS 23.0 was used to analyze the results.

Results: Vitamin D levels in all participants were low (19,84±6,33 ng/ml, NV > 30ng/ml) but the DM group (17,90±5,06 ng/ml) was more deficient than both the IFG (21,08±7,45 ng/ml, p=0.007) and CG group (19,91±5,12 ng/ml, p=0.036). Testosterone levels in all participants were in the low normal range (377,42±150,22ng/dl, NV=300-1050 ng/dL). Both the DM (328,36±127,54 ng/dL, p=0.01) and the IFG group (379,96±130,19 ng/dL, p=0.036) had lower levels than the CG (428,75±180,78 ng/dL) with a statisti-cally significant difference between the IFG and CG groups (p=0.034). No correlation was found between testosterone and vitamin D levels in the IFG group or in any other group. In the IFG group testosterone levels correlated negatively and significantly with obesity indices (BMI r=-0.326** p=0.009, Waist circumference r=-0.377* p=0.003) insulin resistance indices (Fast-ing insulin r=-0.389* p=0.002, HOMA r=-0.302* p=0.016) and FG (r=-0.339*

p=0.013) and correlated positively with HDL cholesterol (r=0.362* p=0.007). In this group, vitamin D levels were negatively correlated with FG (r=-0.260**

p=0.010), total cholesterol (r=-0.279**, p=0.005) and triglycerides (r=-0.223**

p=0.027).Conclusions: Testosterone levels in elderly individuals with IFG correlate

with indices of glucose metabolism dysregulation. This association is evi-dent before overt DM emerges and is independent of vitamin D levels.

2019‑PThe Role of Glucagon in Gastrointestinal‑Mediated Glucose Dis‑posal and Incretin Effect in Patients with Type 2 Diabetes and Nor‑mal Glucose Tolerant IndividualsSOFIE HÆDERSDAL, ASGER LUND, ELISABETH NIELSEN-HANNERUP, HENRIK MAAGENSEN, JENS JUUL HOLST, FILIP K. KNOP, TINA VILSBØLL, Hellerup, Denmark, Copenhagen, Denmark

Gastrointestinal-mediated glucose-disposal (GIGD) after oral glucose tol-erance test (OGTT) reflects the percentage of glucose disposal caused by the oral route. GIGD is reduced in patients with type 2 diabetes (T2D) because of a reduced incretin effect, but possibly also due to hyperglucagonemia. Uti-lizing the glucagon receptor antagonist (GRA), LY2409021, we investigated the effect of glucagon on GIGD, incretin effect and plasma glucose (PG). In a double-blinded, randomized, cross-over study, ten middle-aged, obese T2D patients and ten controls (CTRL) underwent two 50g-OGTTs with preceding

2015‑PExendin‑4, a Glucagon‑Like Peptide‑1 Receptor Agonist, Attenu‑ates Breast Cancer Growth via Inhibiting NF‑kB ActivationCHIKAYO IWAYA, TAKASHI NOMIYAMA, SHIHO KOMATSU, TAKAKO KAWA-NAMI, YURIKO HAMAGUCHI, TOMOKO TANAKA, TOSHIHIKO YANASE, Fukuoka, Japan

Incretin therapy has received much attention, because of its’ tissue pro-tective effects beyond glycemic control. In Japan, cancer is the most criti-cal cause of death in patients with diabetes. We have previously reported anti-prostate cancer effect (Diabetes 2014, PLOS ONE 2015) of Exendin-4 (Ex-4). On the other hand, breast cancer is one of the most popular cancers in female patients with type 2 diabetes and obesity. Then, we next examined whether GLP-1 action could attenuate breast cancer. In human breast can-cer cell lines, MCF-7, MDA-MB-231 and KPL-1 cells, GLP-1R was expressed, and 0.1~10nM Ex-4 significantly decreased the number of breast cancer cells in dose-dependent manner. Although Ex-4 did not induce apoptosis, BrdU assay revealed that Ex-4 attenuates cell proliferation of breast cancer cells dose-dependently. If we transplanted MCF-7 cells into nude mice subcutane-ously and treated them with 300pM/kg/day Ex-4 for 9 weeks, we observed decreased tumor size of MCF-7 in Ex-4-treated mice. Immunohistochemistry with Ki67, a marker of cell proliferation, revealed that breast cancer cell proliferation was significantly reduced in tumor extracted mice treated with Ex-4. It is well known that NF-kB is constitutively activated in cancers such as breast cancer and contributes to cancer cell survival and development. In MCF-7 cells, Ex-4 significantly inhibited the translocation of NF-kB (p65) into nucleus and its’ transcriptional activity. Gene expression of IL-8, VEGF and COX-2, target genes of NF-κB in breast cancer, was significantly reduced by Ex-4. Further, Ex-4 decreased phosphorylation of both Akt and IkB. These data suggest that GLP-1 could attenuate breast cancer cell proliferation via inhibiting NF-kB activation.

Supported By: Eli Lilly and Company

2016‑PSGLT2 Inhibitor Ipragliflozin Inhibits Breast Cancer via Membrane HyperpolarizationSHIHO KOMATSU, TAKASHI NOMIYAMA, TOMOHIRO NUMATA, TAKAKO KAWANAMI, YURIKO HAMAGUCHI, KIRIKO TAKAHASHI, TOMOKO TANAKA, RYUJI INOUE, TOSHIHIKO YANASE, Fukuoka, Japan

Currently, the leading cause of death in Japanese patients with diabe-tes is cancer. We have previously reported the anti-prostate cancer effect (Diabetes 2014, PLOS ONE 2015) of Exendin-4. On the other hand, SGLT2 inhibitor has recently come into clinical use and been receiving much atten-tion for its action to prevent cardiovascular events. However, the anti-cancer effect of SGLT2 inhibitor is still under elucidation. In the present study, we examined the anti-cancer effect of SGLT2 inhibitor ipragliflozin (Ipra) using a breast cancer model. In human breast cancer cell lines, MCF-7 cell, SGLT2 expression was detected using both RT-PCR and immunohistochemistry. 1-50nM Ipra significantly and dose-dependently suppressed the growth curve of MCF-7 cells. BrdU assay revealed that Ipra attenuates the prolif-eration rate of MCF-7 in a dose dependent manner. Further, apoptosis was also induced by Ipra in Tunel assay. Because the anti-breast cancer effect of Ipra was completely canceled by knocking down of SGLT2, this effect could be induced by SGLT2 inhibition by Ipra. We next measured membrane potential and whole cell current using the patch clamp technique. When we treated MCF-7 cell with Ipra or glucose free medium, membrane hyperpolar-ization was observed. In addition, the replacement of sodium with NMDG and knock-down of SGLT2 by siRNA suppressed glucose induced whole cell current of MCF-7 cell, suggesting that Ipra inhibits sodium and glucose incorporation through SGLT2. These data suggest that SGLT2 inhibitor Ipra induces apoptosis in the breast cancer cell, MCF-7, via inhibiting sodium and glucose incorporation.

2017‑PGlucagon Receptor Antagonism Lowers Fasting Glucose but Not Postprandial Glucose Excursions in Patients with Type 2 DiabetesSOFIE HÆDERSDAL, ASGER LUND, HENRIK MAAGENSEN, ELISABETH NIELSEN-HANNERUP, JENS JUUL HOLST, FILIP K. KNOP, TINA VILSBØLL, Hellerup, Denmark, Copenhagen, Denmark

Type 2 diabetes (T2D) pathophysiology includes hyperglucagonemia and increased endogenous glucose production. We investigated the effects of the glucagon receptor antagonist (GRA) LY2409021, on plasma glucose (PG) excursions in patients with T2D and nondiabetic controls. In a double-blinded, randomized, cross-over study, middle-aged patients with T2D (n=10, BMI [mean±standard error of mean]: 33.0±1.7 kg/m2; HbA1c: 46.2±1.9

A533


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



Methods: Human islets were isolated from deceased nondiabetic donors and treated in quadruplicate with 1 mM or 6 mM glucose with or without dapagliflozin (12 μM) for 1 h. Healthy male C57BL/6J mice were treated with one-shot dapagliflozin (10 mg/kg of body weight n= 30) or vehicle (n=30) after an overnight fast. Glucagon secretion was measured by ELISA.

Results: Islets from 26 donors (BMI range, age range, HbA1c range) were studied. Mean glucagon secretion was 6,06±5,70% of content (range 16,17% to 0,27%) at 1mM and decreased to 3,68±3,56% of content (range 12,37% to 0,23%) at 6mM. However, donor effect was a major determinant of glucagon secretion (p<0.0001). When analyzed with two way ANOVA, dapagliflozin significantly induced glucagon secretion at 6mM to 6,16±5,58% of content (range 22,99% to 0,42%), (p<0.0001, dapagliflozin/donor interac-tion). Sample size analysis predicted that for 80% power with 5% signifi-cance as a measure of sensitivity, the minimal sample size required to draw firm conclusion is n=10 human islet donors. In vivo, dapagliflozin consistently and significantly induced glucagon secretion in C57BL/6J mice (vehicle vs. dapagliflozin; p<0,0001).

Conclusions: The use of human islet cultures for drug testing is recom-mended in conjunction with adequately powered group sizes for dependable preclinical testing of new therapeutic drugs.

Supported By: Conseil Régional Nord-Pas-de-Calais (to C.B.); European Com-mission (FEDER12003944 to F.P.); Fondation de l’Avenir (to F.P.); European Genomic Institute for Diabetes (ANR-10-LABX-46 to F.P.); JDRF

2022‑PMetabolic Effects on Incretin and Glucagon Secretion in Obesity and Type 2 DiabetesKATHARINA S. WEBER, KLAUS STRAßBURGER, GIOVANNI PACINI, MARIA FRITSCH, ALESSANDRA BIERWAGEN, JONG HEE HWANG, JULIA SZENDROEDI, KARSTEN MÜSSIG, MICHAEL RODEN, Düsseldorf, Germany, Padova, Italy, Vienna, Austria

The incretin and glucagon secretion is altered in obesity and type 2 dia-betes (T2D). However, the role of circulating and hepatocellular lipids and of hepatic energy metabolism on glucagon-like peptide-1 (GLP-1), glucose-dependent insulinotropic polypeptide (GIP) and glucagon metabolism is yet unclear.

The effect of ingestion of a standardized liquid mixed meal on plasma GLP-1, GIP and glucagon was investigated in 10 young lean insulin sensitive (CON; age 28±3 years, BMI: 23.2±1.5 kg/m2), 10 age-matched obese insulin resistant (OBE; 31±7 years, 34.3±1.7 kg/m2) and 10 elderly obese patients with T2D (61±7 years, 32.0±2.4 kg/m2). Blood glucose, hormones, free fatty acids and triglycerides were measured in fasting and postprandial state. γ-ATP, inorganic phosphate (Pi) and hepatic fat content (HCL) were quantified by 31P/1H magnetic resonance spectroscopy. Adipose tissue insulin sensi-tivity was derived by mathematic modelling of free fatty acid and insulin levels. Partial Pearson correlations adjusted for group effect, age, sex and BMI were calculated.

GLP-1 [pmol/l] was lower in T2D vs. CON at fasting (0.4 (1.8) vs. 1.4 (2.3)) and 260 min (0.4 (2.5) vs. 1.5 (2.8)), while GIP [pg/ml] was lower in OBE com-pared to both CON and T2D at 260 min (OBE: 88.8 (1.8), CON: 204.7 (1.7), T2D: 197.7 (1.4)) (all P<0.05). The area under the concentration curves (AUC) of GLP-1, GIP and glucagon were similar between groups [geometric means (geometric SD)].

Higher AUC0-180 of GIP correlated with higher triglycerides (fasting: r=0.53,

AUC0-180: r=0.59, both P<0.01). The GLP-1 effect, calculated as ratio of β-cell function to AUC of GLP-1, was related to fasting Pi/γ-ATP (r=0.56, P<0.01). AUC0-180

of glucagon correlated with γ-ATP (r=-0.40 P<0.05), Pi (r=-0.43, P<0.05) and HCL (r=0.56, P<0.01) at 160 min and with adipose tissue insulin sensitivity (r=-0.71, P<0.001).

In conclusion, circulating triglycerides associate with GIP secretion, whereas hepatic energy metabolism may affect GLP-1 and glucagon secretion.

2023‑PGlucose‑Dependent Insulinotropic Polypeptide (GIP) Inhibits Bone Resorption In C‑Peptide‑Negative Patients with Type 1 DiabetesMIKKEL CHRISTENSEN, ASGER LUND, SALVATORE CALANNA, NIKLAS R. JØR-GENSEN, JENS JUUL HOLST, TINA VILSBØLL, FILIP K. KNOP, III, Copenhagen, Denmark, Hellerup, Denmark

The insulinotropic gut hormone GIP is released upon food ingestion and has been shown to inhibit bone resorption by almost 50% in healthy young males as assessed by reduction in circulating levels of the bone resorption marker C-terminal telopeptide of type I collagen (CTX). It is unclear, whether this occurs independently of GIP’s insulinotropic effect; and whether GIP

single-dose administration of 100 mg GRA or placebo, respectively, and two corresponding isoglycemic iv glucose infusions (IIGIs). Compared to placebo, GRA reduced fasting PG (FPG) by 2.4±0.4 mM (P=0.0001) in patients and by 0.6±0.04 mM (P<0.0001) in CTRL. PG excursions during OGTT assessed by incremental area under the curve were greater with GRA compared to pla-cebo for both groups (T2D: 998±64 vs. 694±66, P=0.0004; CTRL: 307±40 vs. 209±44 pM × min, P=0.005). No differences were observed between GRA and placebo on GIGD or the incretin effect.

In conclusion, FPG was lowered by LY2409021 in T2D patients and CTRL, but baseline-subtracted PG excursions increased with GRA. GIGD and incre-tin effect are unaffected by glucagon receptor antagonism.

Supported By: Novo Nordisk Foundation; Eli Lilly and Company

2020‑PIncreased Activin A and Follistatin Levels in Patients with Predia‑betes and DiabetesYA WEN LU, CHIEN YI HSU, CHIN SUNG KUO, PO HSUN HUANG, Taipei, Taiwan

Objective: Activin A and its binding protein follistatin are suggestive to be crucial in glucose homeostasis, and has been recognized as multifunc-tional proteins mediating both inflammatory and anti-inflammatory effects. However, clinical data on activin A and follistatin levels in patients with prediabetes and diabetes are lacking. Here, we investigated activin A and follistatin levels in a community-based study to explore their association with prediabetes and diabetes.

Methods: Totally, 470 inhabitants of I-Lan County in Taiwan with mea-surement of serum activin A and follistatin levels were enrolled (235 men; mean age 69 ± 9 years). We stratified study subjects into normal glucose, prediabetes and diabetes groups, and analyzed the association between activin A, follistatin and blood glucose status.

Results: Age, body mass index, waist circumference, hypertension, sys-tolic blood pressure, fasting glucose, insulin resistance, uric acid level, and urine albumin to urine creatinine ratio were increased in patients with pre-diabetes and diabetes (P for trend <0.05). The serum activin A levels were significantly elevated in prediabetes and diabetes subjects (normal glucose vs. prediabetes vs. diabetes: 491.2±165.3 vs. 559.0±178.5 vs. 572.2±167.0 pg/ml; p < 0.001). Moreover, elevated follistatin levels were observed in pre-diabetes and diabetes groups (normal glucose vs. prediabetes vs. diabetes: 1513±586.3 vs. 1577.4±523.1 vs. 1803.7±802.5 pg/ml; p < 0.001). Multivari-able logistic regression model showed activin A was associated with predia-betes or diabetes independently from age, gender, follistatin, and other risk factors, (odds ratio 1.57 95% CI 1.03-2.40, p = 0.038).

Conclusion: Serum Activin A levels are elevated in patients with prediabe-tes and diabetes than those with normal glucose. Further studies are needed to verify these findings and make clear underlying mechanisms.

Supported By: Taiwan Ministry of Science and Technology; Taiwan and Taipei Veterans General Hospital

2021‑PAnalysis of Heterogeneity of Individual Donor and Islet Glucagon Responses to the SGLT2 Inhibitor DapagliflozinCHIARA SAPONARO, VALERY GMYR, ERICKA MOERMAN, NATHALIE DELAL-LEAU, JULIEN THEVENET, GIANNI PASQUETTI, FRANÇOIS PATTOU, JULIE KERR-CONTE, CAROLINE BONNER, Lille, France

Background: Human islets have become a critical resource for research-ers studying islet physiology and hormone secretion. Notably, donor islet heterogeneity influences the development of diabetes and its response to treatment, and often poses a high risk of data reproducibility and misinter-pretation compared to rodent islets. Dapagliflozin (an SGLT2 inhibitor) has been shown to elevate plasma glucagon levels. The aim of this study was to determine the reproducibility of dapagliflozin-induced glucagon secretion across a large number of donors.

A534


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



lower IGF-1 than AAb- FDR (256 ± 128 ng/mL vs. 357 ± 161 ng/mL, p<0.05), primarily due to decreased levels in the multiple AAb+ FDR group (222 ± 120 ng/mL, p<0.001). Although serum IGF-1 of AAb+ FDR increased with age (r=0.36, p<0.01), this dynamic curve was fit lower (p<0.0001) than that of AAb- controls (r=0.45, p<0.001). Additionally, we observed that IGF-2 was decreased in new onset T1D (691 ± 291 ng/mL, p<0.001) as compared to AAb- FDR (1125 ± 758 ng/mL). Again, AAb+ FDR had lower IGF-2 than AAb- FDR (744 ± 546 ng/mL vs. 1125 ± 758 ng/mL, p<0.01), although these decreased levels remained significant in both multiple AAb+ (757 ± 674 ng/mL, p<0.05) and single AAb+ FDR (731 ± 406 ng/mL, p<0.05). These data support the notion that insufficient levels of IGF-1 and -2 may contribute to the pathogenesis of T1D. Furthermore, the observation of decreased IGF-1 and IGF-2 levels prior to disease onset suggest these may serve as novel disease biomarkers.

Supported By: National Institutes of Health (P01AI42288 to M.A.A., T.M.B.), (R01DK106191 to T.M.B.); JDRF (2012-280 to T.M.B.)

2026‑PIGFBP2 Disrupts Colonic Stem Cell Growth and Facilitates the Onset of Diabetic EnteropathyCRISTIAN LORETELLI, FRANCESCA D’ADDIO, ANNA MAESTRONI, VERA USUELLI, MOUFIDA BEN NASR, SERGIO DELLEPIANE, EDUARDO CASTILLO LEON, EDI VIALE, DOMENICO CORRADI, GIAN VINCENZO ZUCCOTTI, PAOLO FIORINA, Milan, Italy, Boston, MA, Parma, Italy

The existence of a hormonal control for stem cells and in particular for colonic stem cells (CoSCs) in individuals with long-standing type 1 diabetes (T1D) and intestinal disturbances, namely diabetic enteropathy (DE) has been recently established. The IGFBP3/TMEM219 axis has been demonstrated to be dysfunctional in DE, but whether it is the sole factor involved remains to be elucidated. Here we report that Insulin-like growth factor binding 2 protein (IGFBP2), that binds free insulin-like growth factor-1 (IGF-1), is one of the top increased low-abundance protein in long-standing T1D at proteomic analysis and targeted immunoassay. IGFBP2 levels correlate with intestinal symptoms of DE according to GSRS score. We then explored the effect of IGFBP2 on CoSCs in vitro by using the mini gut assay. IGFBP2 administra-tion remarkably reduced CoSCs self-renewal properties in cultured healthy mini-guts. Finally, RNA-seq revealed an altered machinery of cell metabo-lism in IGFBP2-exposed mini-guts. This effect was accompanied by a parallel decrease in CoSC markers (EphB2, LGR5, Aldh). A reduction in CoSC mRNA and protein levels (as evaluated with immunofluorescence, Western blot and FACS) and a failure to generate mini-guts in vitro were likewise evident in T1D individuals as compared to healthy subjects. We are currently testing the different known IGFBP2 receptors as potential molecular mediators of IGFBP2-regulated CoSC homeostasis, as well as a number of unknown puta-tive ligands that will be identified by a combined immunoprecipitation/pro-teomic approach. Interestingly, we observed a near-normalization of IGFBP2 serum levels after the achievement of normoglycemia through simultaneous kidney-pancreas transplantation at 8 years of follow-up, with a significant improvement in DE signs and symptoms. These findings demonstrate that IGFBP2 is a novel enterostaminine which acts as a regulating hormone on CoSC homeostasis and which is dysfunctional in T1D and DE.

Supported By: Società Italiana di Diabetologia; European Association for the Study of Diabetes; European Foundation for the Study of Diabetes; American Heart Association

2027‑PSomatostatin Regulates GLP‑1 Secretion through the Somatostatin Subtype 2 ReceptorSARA L. JEPSEN, MARIA N. GABE, RUNE E. KUHRE, NICOLAI J. WEWER ALBRECHTSEN, JOHANNE WINNELØV, METTE M. ROSENKILDE, JENS PEDER-SEN, CAROLYN DEACON, JENS JUUL HOLST, Copenhagen, Denmark

Somatostatin (SS) is a peptide hormone that inhibits the secretion of glu-cose- and appetite-regulating hormones. It exists in two isoforms SS-14 and SS-28. Previous studies have suggested that SS inhibits the secretion of the incretin hormone, glucagon-like peptide-1 (GLP-1) by binding to the family of SS receptors (SSTrs), denoted SSTr1-5. It is unknown which of the five receptors that regulates GLP-1 secretion and we investigated the possibility that the inhibition is mediated via SSTr2. First, we measured protein lev-els of SS in intestinal biopsies from mice (n=9) and show that SS is equally expressed from the proximal to the distal intestine (~40±15pmol/g) except for the caecum (8±5 pmol/g). To assess the impact of SS on GLP-1 secretion, we isolated and perfused the proximal small intestine from mice with SS-14 and 28 and subsequently measured GLP-1 levels in the venous effluents. Intra-arterial administration of 0.01, 0.1, and 1nM SS-14 (n=6) reduced in a

affects other markers of bone turnover e.g., N-terminal propeptide of type 1 procollagen (P1NP) and parathyroid hormone (PTH).

In a randomized, double-blinded, cross-over study, we investigated the effect of exogenously administered GIP (4 pmol/kg/min) or matching placebo (saline) in 10 male C-peptide-negative patients with type 1 diabetes (age [mean±SD]: 26±4 years; BMI: 24±2 kg/m2; HbA1c 7.3±0.8% (57±9 mmol/mol). On four separate days where plasma glucose was clamped at 12 mM for 90 minutes or gradually lowered by insulin and then raised again (plasma glucose between 3-7 mM for 120 minutes), we measured CTX, P1NP and PTH with 30-minute intervals.

During hyperglycemia, from similar baseline levels (mean±SD) of 0.38±0.26 μg/L, GIP suppressed CTX by 59±19% compared to 7±9% during saline infusion (P<0.0001). During low plasma glucose, again from similar baseline levels of 0.45±0.28 μg/L, GIP suppressed CTX by 59±18% compared to 24±10% on the saline day (P<0.0001). P1NP and PTH did not differ signifi-cantly between GIP and placebo days (all comparisons P>0.27).

We conclude that GIP robustly reduces bone resorption (estimated by CTX) independently of insulin and during both elevated and low plasma glu-cose levels, but has no effect on P1NP or PTH.

2024‑PPancreatic Amylase and Lipase Plasma Concentrations Are Unaf‑fected by Intravenous GLP‑1 Infusion in Patients with Type 1 and 2 Diabetes as well as in Healthy ControlsDAVID P. SONNE, JONATAN I. BAGGER, JENS J. HOLST, TINA VILSBØLL, FILIP K. KNOP, Hellerup, Denmark, Copenhagen, Denmark

Recent clinical trials (LEADER, SCALE, SUSTAIN) have found that gluca-gon-like peptide-1 (GLP-1) receptor agonists (GLP-1RA) induce increases in plasma concentrations of amylase and lipase. In some patients, concentra-tions of three times the upper limit of the normal range or more have been reported. The mechanism behind this effect is not fully understood. Possibly, elevated GLP-1RA concentrations in plasma may be the direct cause. We examined the effects of intravenous infusion of GLP-1, resulting in plasma GLP-1 concentrations high in the physiological range, on pancreas-specific amylase and lipase concentrations in plasma. Amylase and lipase concen-trations were measured with enzyme colorimetric assays in plasma from 9 patients with type 1 diabetes, 10 patients with type 2 diabetes and 10 con-trol subjects undergoing a continuous 3.5-hour infusion with saline or low, medium or high GLP-1 (0.2, 0.4 and 0.8 pmol/kg/min). A stepwise glucose infusion was used to clamp plasma glucose concentrations at different lev-els (from fasting to 15 mM). In all groups, fasting amylase and lipase concen-trations were within normal range. GLP-1 infusions resulted in steady-state GLP-1 plasma concentrations of ~20, ~30 and ~50 pM. Amylase and lipase concentrations did not change in response to any of the GLP-1 infusions in any of the groups. Patients with type 2 diabetes and controls had compa-rable concentrations of amylase (range 18-29 U/l) and lipase (range 26-44 U/l), whereas patients with type 1 diabetes had slightly lower amylase and lipase concentrations (range 12-16 U/l and 16-29 U/l, respectively). These results suggest that short-term GLP-1 infusion is unable to affect plasma concentrations of amylase and lipase. Possibly, long-term treatment with GLP-1RAs may induce trophic effects on pancreatic acini leading to acinar secretion rather than damage.

Supported By: Novo Nordisk Foundation

2025‑PDiminished Insulin‑Like Growth Factors in Pre‑Type 1 DiabetesMELANIE R. SHAPIRO, CLIVE H. WASSERFALL, SEAN M. MCGRAIL, MICHAEL J. HALLER, DESMOND A. SCHATZ, MARK A. ATKINSON, TODD M. BRUSKO, Gainesville, FL

Type 1 diabetes (T1D) is believed to result from deficiencies in immunoreg-ulation together with impairments in beta cell viability and function. Since insulin-like growth factors (IGF) promote regulatory T cell proliferation in addition to endocrine and exocrine pancreatic growth, we hypothesized that either of the two IGF-family ligands, IGF-1 and IGF-2, may be downregulated in T1D, particularly during the period prior to disease onset. Total serum IGF-1 and -2 levels were measured in an age-matched (range 2-20 years old), cross-sectional cohort of autoantibody negative (AAb-) controls (n=60); AAb- first-degree relatives (AAb- FDR, n=47); FDR positive (AAb+ FDR) for one (n=28) or multiple (n=26) of GAD65, IA-2, or ZnT8 AAbs; new-onset patients within 3 months of diagnosis (n=62, duration 1.00 ± 0.71 months); and established T1D patients (n=66, duration 4.39 ± 3.77 years). IGF-1 lev-els were significantly lower in AAb+ FDR (256 ± 128 ng/mL, p<0.0001), new onset T1D (308 ± 137 ng/mL, p<0.001), and established T1D (295 ± 168 ng/mL, p<0.001) patients than AAb- controls (421 ± 183 ng/mL). AAb+ FDR had

A535


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



three other days (day B: 30.5±7.1 g, day C: 36.5±5.1 g, and day D: 39.1±7.3 g). Steady-state plasma levels of GIPR-An and GIP amounted to ~50 nM and ~90 pM, respectively. Elimination plasma half-life of GIP(3-30)NH2 was 7.6±1.4 min (mean±SD). GIP-induced insulin secretion (day A, incremental AUC0-40

min (mean±SEM): 29.3±3.4 nM × min) was significantly (P<0.0001) diminished on day C (GIP+GIPR-An) (12.4±1.7 nM × min) corresponding to an inhibition of GIP-induced insulin secretion by the GIPR-An of 80.7±14.4% (mean±SD). There was no effect of the GIPR-An alone (day B: 6.6±1.1 nM × min, day D: 8.1±0.9 nM × min). No effects of GIP and/or GIP(3-30)NH2 on glucagon, glucagon-like peptide-1, triglycerides, cholesterol, glycerol or free fatty acids were observed.

The naturally occurring GIP fragment, GIP(3-30)NH2, is an efficacious GIPR-An in humans, when administered in supraphysiological doses.

Supported By: European Association for the Study of Diabetes; Gangstedfon-den; Aase og Ejnar Danielsens Foundation

2030‑PThe Adipo‑Regulatory and the Vasodilatory Effects of Glucose‑Dependent Insulinotropic Polypeptide (GIP) Are Abolished by the High‑Affinity Competitive Antagonist of the Human GIP Receptor: GIP (3‑30) Nh2MEENA ASMAR, ALI ASMAR, LENE SIMONSEN, METTE M. ROSENKILDE, BOLETTE HARTMANN, LÆRKE GASBJERG, FLEMMING DELA, JENS BÜLOW, JENS JUUL HOLST, Copenhagen, Denmark

Objective: Recently, it was demonstrated that a truncated form of GIP, GIP(3-30)NH2, is a high-affinity competitive antagonist of the human GIP receptor. This human study examined the efficacy of GIP(3-30)NH2 as an antagonist of GIP and the physiological role of GIP in lipid metabolism.

Methods: Subcutaneous abdominal adipose tissue lipid and glucose metabolism were studied in eight lean healthy volunteers by measuring arte-rio-venous concentrations of metabolites and regional adipose tissue blood flow (ATBF) on three different occasions during infusion of 1) GIP (1.5 pmol/kg/min) 2) GIP(3-30)NH2 (1000 pmol/kg/min) and 3) GIP and GIP(3-30)NH2 - all three days in combination with hyperglycemic-hyperinsulinemic clamps.

Results: During the antagonist, ATBF remained constant throughout the experiment (2.8 ± 0.1 ml min-1 100 g tissue-1), while ATBF increased ~five-fold during GIP (13.7 ± 0.7 ml min-1 100 g tissue-1, P=0.004). During infusion of both the antagonist and GIP, ATBF increased only slightly (5.1 ± 0.4 ml min-1 100 g tissue-1, P=0.02). In adipose tissue, triglyceride (TAG) and glucose uptake decreased, and free fatty acid (FFA)/glycerol ratio increased during the antagonist alone and in combination with GIP (P<0.03). In addition, dur-ing these infusions, insulin levels and the total glucose amount infused were lower (P<0.01). During GIP infusion, insulin levels and the total amount of glu-cose infused were higher (P<0.01), TAG and glucose uptake increased while FFA output and FFA/glycerol ratio decreased (P<0.02).

Conclusion: During the GIP receptor antagonist, ATBF remained unchanged, while adipose tissue TAG uptake decreased compared to GIP alone, indicat-ing that GIP plays a crucial role in lipid metabolism. The changes in glucose infusion rates and insulin demonstrate an effect of the antagonist also on the incretin effect of GIP.

2031‑PAntifibrotic Effect of Linagliptin in the Canine Model of Atrial FibrillationTAZURU IGARASHI, SHINICHI NIWANO, HIROE NIWANO, HIRONORI NAKA-MURA, NARUYA ISHIZUE, TAMAMI FUJIISHI, TOMOHARU YOSHIZAWA, AKIRA SATOH, JUN KISHIHARA, MASAMI MURAKAMI, HIDEHIRA FUKAYA, JUNYA AKO, Sagamihara, Japan, Machida, Japan

Background: Dipeptidyl peptidase-4 (DPP-4) inhibitors have been reported to exhibit cardioprotective effects in some pathological conditions. But their effect in atrial remodeling, such as in construction of arrhythmogenic sub-strate of atrial fibrillation (AF), remains unclear. In this study, the effect of linagliptin against the atrial remodeling was evaluated in a canine AF model.

Methods: Sixteen dogs with atrial rapid stimulation were divided into linagliptin (9mg/kg/day, n=8) and control (n=8) groups. In each group, con-tinuous rapid pacing was performed for 3 weeks. Atrial effective refractory period (AERP), conduction velocity (CV), and AF inducibility were evaluated in every week during the 3 week protocol. Similarly, blood was sampled to measure MCP1 level. After the protocol, atrial tissues were sampled for HE, Azan and dihydroethydium (DHE) staining to evaluate tissue damage and oxidative stress.

Results: The control exhibited gradual AERP shortening and CV decrease along the time course. In the linagliptin group, AERP shortening was not affected, but CV decrease was suppressed in comparison with the control

dose-dependent manner GLP-1 secretion (0.01nM p=0.5, 0.1nM p=0.2, 1nM p<0.01). SS-28 (n=6) also inhibited GLP-1 secretion and more potently com-pared to SS-14 (0.01nM p=0.3, 0.1nM p=0.011, 1nM p=0,014). In COS-7 cells transiently transfected with mouse SSTr2, the SSTr2 antagonist PRL2915 had an 11-fold lower affinity (Ki of 11nM, logKi -6.6±0.2, n=3) compared to SS-14 (1nM, logKi -8.9±0.2, n=3). Using an Inositol triphosphate (IP3) assay, PRL2915 inhibited SS-14 mediated IP3 accumulation in cells express-ing mSSTr2 with a potency of 301nM (logIC50 -6.5+/-0.1, n=3) and had no intrinsic activity when applied alone (n=3). No inhibition by PLR2915 of SS-14 activity was observed on SSTr1, 3, 4, and 5. When PRL2915 was added to the perfused mouse intestine (n=6), intra-arterial infusion of 100nM, 1μM and 10μM, showed a dose-dependent increase in GLP-1 secretion (100nM; p=0.3, 1μM; p=0.02, 10μM; p<0.001).

In conclusion, our results demonstrate that the SS/SSTr system and in par-ticular the SSTr2, plays an important role in the regulation of GLP-1 secretion.

2028‑PThe Impact of Short‑Chain Fatty Acids on Glucagon‑Like‑Peptide‑1 Secretion from the Isolated Perfused Rat ColonCHARLOTTE B. CHRISTIANSEN, MARIA N. GABE, BERIT SVENDSEN, THUE W. SCHWARTZ, METTE M. ROSENKILDE, JENS J. HOLST, Copenhagen, Denmark

The colonic epithelium harbors a large number of endocrine cells, but little is known about the endocrine functions of the colon. However, high den-sity of the GLP-1 and PYY secreting L-cells is of great interest because of the potential antidiabetic and anti-obesity effects of GLP-1 and PYY. Short chain fatty acids (SCFAs) are produced by distal bacterial fermentation and are suggested to activate the colonic free fatty acid receptors GPR41 and GPR43, stimulating the distal L-cells. We used the isolated perfused rat colon as a model of colonic endocrine secretion and studied the effects of the predominant SCFAs formed: acetate, propionate and butyrate. We show that luminal and especially vascular infusion of acetate and butyrate signifi-cantly increase colonic GLP-1 secretion (p<0.05), and to a minor extent also PYY secretion. Propionate neither affects GLP-1 nor PYY secretion whether administered luminally or vascularly. A GPR41 and a GPR43 specific agonist showed no impact on colonic GLP-1 or PYY secretion, and a GPR41 antagonist did not decrease the SCFA-induced GLP-1 response. However, the voltage-gated Ca2+-channel blocker nifedipine (p<0.05) and the KATP channel opener diazoxide (p<0.02) completely abolish the responses. Finally, an IP3 assay conducted on transfected COS-7 cells expressing GPR43 (Gq coupled) shows low-potent partial weak agonism of acetate, propionate, and butyrate with EC50 and Emax values of 0.3-0.8 mM and 47-68%, respectively, compared to the GPR43 specific agonist which is a full agonist with around 1000-fold higher potency than the SCFAs (EC50=0.001 mM).

In conclusion, we find that SCFAs increase colonic GLP-1 secretion and that GPR41/43 are not necessarily involved in the mechanism behind. We believe that the SCFAs are metabolized and mainly used as a colonocyte energy source. Further knowledge about function of the numerous colonic endocrine cells may prove important for the understanding of the patho-physiology of diabetes and obesity.

Supported By: Lundbeck Foundation; Danish Diabetes Academy; Novo Nordisk Foundation

2029‑PGIP(3‑30)NH2 Is an Efficacious GIP Receptor Antagonist in HumansLÆRKE S. GASBJERG, AMALIE R. LANNG, BOLETTE HARTMANN, ALEXANDER H. SPARRE-ULRICH, FLEMMING DELA, MIKKEL CHRISTENSEN, TINA VILSBØLL, JENS JUUL HOLST, METTE M. ROSENKILDE, FILIP K. KNOP, Copenhagen, Denmark, Hellerup, Denmark

Glucose-dependent insulinotropic polypeptide (GIP) is an incretin hormone secreted from enteroendocrine K cells in the postprandial state. GIP stimu-lates insulin and glucagon secretion glucose-dependently. In addition, GIP may inhibit bone resorption and stimulate fat deposition. GIP physiology in humans remains relatively poorly characterized, mainly because until now, a GIP receptor antagonist (GIPR-An) has not been available for use in humans. We previously showed that a naturally occurring GIP fragment (GIP(3-30)NH2) acts as a human GIPR-An in vitro. We aimed to establish GIP(3-30)NH2 as a GIPR-An in humans.

Insulin secretion was evaluated during four separate days in 10 healthy men (age 21.6±1.7 years, BMI 22.7±1.3 kg/m2). They received a 45-minute infusion of the GIPR-An (800 pmol/kg/min), GIP (1.5 pmol/kg/min) and/or pla-cebo during a hyperglycemic clamp in a randomized, crossover design (day A: GIP; day B: GIPR-An; day C: GIP+GIPR-An; day D: Placebo).

To clamp plasma glucose levels on ~12 mM, we used significantly larger amounts of glucose (mean±SD: 54.7±14.1 g) on day A (GIP) compared to the

A536


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



2034‑PInositol 1,4,5‑Trisphosphate Receptor‑1 (IP3R1) Mediates Gluca‑gon‑Stimulated Gluconeogenesis and Mitochondrial OxidationRACHEL J. PERRY, YONGLIANG WANG, SYLVIE DUFOUR, LIANG PENG, BARBARA E. EHRLICH, GERALD I. SHULMAN, New Haven, CT

While it is well established that glucagon stimulates hepatic glycogenoly-sis through activation of a G protein-coupled receptor leading to increases in cAMP and activation of protein kinase A, much less is known regarding the mechanism by which glucagon stimulates hepatic gluconeogenesis and mitochondrial oxidation and the potential roles of intracellular calcium and IP3R1 in these processes. In order to examine these questions we studied mice with liver-specific deletion of IP3R1 (LKO). Although LKO mice were euglycemic after an overnight fast, following an infusion of glucagon designed to increase plasma glucagon concentrations ~5 fold, plasma glu-cose concentrations were 40 mg/dL higher in wild type (WT) mice relative to LKO (P<0.0001). The effect of the glucagon infusion to increase endogenous glucose production was also abrogated in LKO mice ([LKO pre-glucagon: 16.4±0.9 mg/(kg-min), post-glucagon: 15.4±0.9 mg/(kg-min)] compared to WT mice [pre-glucagon: 15.6±1.1 mg/(kg-min), post-glucagon: 19.2±1.0 mg/(kg-min)], P=0.02 post-glucagon]. Finally, to examine the potential role for intracellular calcium and IP3R1 in glucagon’s effects on hepatic mitochon-drial oxidation we assessed in vivo rates of hepatic mitochondrial citrate synthase flux (VCS) with a novel combined GC-MS/NMR method using mass isotopomer distribution analysis of liver [13C]glucose following an infusion of [3-13C]lactate and glucagon. We found that hepatic VCS flux was ~75% lower in glucagon-treated LKO mice compared to WT mice [LKO: 44±7 μmol/(kg-min), WT: 203±48 μmol/(kg-min), P=0.01]. Taken together, these data demonstrate that calcium signaling through IP3R1 is necessary to mediate glucagon’s stimulatory effect on both hepatic mitochondrial oxidation and gluconeogenesis. Given the key roles for inappropriate hyperglucagonemia and increased gluconeogenesis in the pathogenesis of type 2 diabetes, IP3R1 represents a novel therapeutic target.

Supported By: National Institutes of Health (R01DK40936, R01AG-23686, P30DK45735, T32DK101019)

2035‑P25‑Hydroxy Vitamin D and Osteocalcin Are Independently Associ‑ated with Glucose Metabolism in Type 2 Diabetes PatientsSU JUNLEI, Shanghai, China

Introduction: Previous studies have investigated the respective associa-tions of 25-hydroxyvitamin D (25(OH)D) and osteocalcin (OC) with glucose metabolism. However, vitamin D and OC is indicated to have interaction, our aim was to explore whether 25(OH)D or OC had modulating effects on their associations with glucose metabolism in patients with type 2 diabetes mellitus (T2DM).

Methods: A total of 582 men and 554 women with T2DM were recruited. Serum 25(OH)D, OC and parameters of glucose metabolism were measured, covariance analysis and multiple linear regression analysis were performed.

Results: The associations of OC with parameters of glucose metabolism were not changed by vitamin D statuses (25(OH)D<50 nmol/L and 25(OH)D≥50 nmol/L) in men or women with T2DM. In addition, the associations of 25(OH)D with parameters of glucose metabolism did not differ in OC tertiles. 25(OH)D and OC had respective and favorable associations with variables of glucose metabolism in men and women with T2DM, but the associations of 25(OH)D with these variables were not substantially changed after exclud-ing the influence of OC, vice versa.

Conclusions: 25(OH)D or OC do not have modulating effects on their asso-ciations with glucose metabolism in T2DM patients, they are associated with glucose metabolism independent of each other. Further prospective studies are needed to clarify the interplay among vitamin D, OC, and glucose homeostasis in T2DM patients.

Supported By: Shanghai Municipal Natural Science Foundation (13ZR1432100); National High Technology Research and Development Program (2013AA032203); National Natural Science Foundation of China (81500650)

2036‑PFGF‑21 Plays an Autocrine Role after β‑Adrenergic Stimulation in AdipocytesSARAH JUSTESEN, KIRSTEN V. HAUGEGAARD, BIRGITTE ANDERSEN, Måløv, Denmark

Background: Fibroblast growth factor-21 (FGF-21) and β-adrenergic sig-nalling seem to have overlapping biology and both induce browning and uncoupling protein 1 (UCP1) expression in adipocytes. FGF-21 is furthermore, released from white and brown adipose tissues (WAT and BAT) in response

(p<0.05). The AF inducibility was gradually increased in the control, but such increase was suppressed in the linagliptin group (p<0.05). The control exhibited advance in tissue fibrosis. In contrast in the linagliptin group, the degree of tissue fibrosis was suppressed in comparison with the control. MCP1 level in postsurgical state was lower in the linagliptin group than the control (p<0.05). The DHE staining exhibited suppression of reactive oxygen species (ROS) expression in the linagliptin group, although it was enhanced in the control.

Conclusions: Linagliptin suppressed AF inducibility and CV decrease in the canine AF model. Similarly, MCP1 level was lower and ROS expression was suppressed in the linagliptin group. Linagliptin may suppress AF in the canine model possibly through the antifibrotic effect due to anti-inflammatory and anti-oxidative effects.

2032‑PCell‑Autonomous Light Sensitivity via Opsin 3 Regulates Fuel Utili‑zation in Adipose TissueMARI SATO, XIAOZHI REN, LUIZ O. LEIRIA, CHIH HAO WANG, MATTHEW D. LYNES, KING WAI YAU, YU HUA TSENG, Boston, MA, Baltimore, MD

Opsin 3 (OPN3) is a photosensitive G-protein-coupled receptor (GPCR) reported to signal through Gi, at least when expressed heterologously (Koyanagi et al, 2013, PNAS). Although most opsins are expressed mainly or exclusively in the eyes, OPN3 is expressed at a higher level in adipose tissue than in the eyes. To understand the role of OPN3 in adipose tissue, we exam-ined the metabolic phenotype of OPN3-knockout (OPN3-KO) mice. OPN3-KO mice gained more weight than WT mice despite normal food intake when fed with a high-fat diet. To determine whether this phenotype was caused by impairment in fuel utilization in an adipose-tissue-specific manner, we generated OPN3-KO pre-adipocytes and measured glucose uptake in mature adipocytes after in vitro differentiation. Interestingly, OPN3-KO adipocytes displayed decreased basal, but not insulin-stimulated, glucose uptake compared with wild type (WT) cells. Glucose transporter 1 (Glut1) plays an essential role in basal glucose uptake, and, indeed, Glut1 protein expression was significantly reduced in OPN3-KO adipocytes. Thus, OPN3 appears to regulate Glut1 expression and basal glucose uptake in adipose tissue. To test whether the regulation of Glut1 by OPN3 is light-sensitive, we differ-entiated OPN3-KO and WT pre-adipocytes in the absence or presence of exposure to white LED light for eight days. Both KO and WT cells differenti-ated normally and the expression of adipogenic genes was not altered by light exposure. Intriguingly, light increased basal glucose uptake and Glut1 protein expression in WT cells, but not in OPN3-KO adipocytes.

In summary, adipose cells can directly sense light through OPN3, which induces Glut1 protein and modulates basal glucose uptake in adipose tissue. These data reveal a novel adipose-cell-autonomous light-sensing mecha-nism in the regulation of fuel utilization.

Supported By: Sunstar Foundation

2033‑PThe Vasodilation in Adipose Tissue Induced by Glucose‑Dependent Insulinotropic Polypeptide Involves Recruitment of CapillariesALI ASMAR, MEENA ASMAR, LENE SIMONSEN, JENS JUUL HOLST, JENS BÜLOW, Copenhagen, Denmark

Objective: Glucose-dependent insulinotropic polypeptide (GIP) in combi-nation with hyperinsulinemia increases blood flow and triglyceride clear-ance in subcutaneous abdominal adipose tissue in lean humans. The pres-ent experiments were performed to determine whether the increase may involve capillary recruitment. We investigated microvascular volume in abdominal subcutaneous adipose tissue using real-time, contrast-enhanced, ultrasound imaging in healthy subjects.

Materials and Methods: Eight lean healthy volunteers were studied before and after 1-h infusion of GIP or saline during a hyperglycemic-hyper-insulinemic clamp, raising plasma glucose and insulin to postprandial levels. Abdominal subcutaneous adipose tissue blood flow (ATBF) was determined by the 133Xenon clearance technique, and microvascular volume was studied by contrast-enhanced ultrasound imaging.

Results: During GIP infusion and the clamp, ATBF increased ~five-fold (13.1 ±0.8 ml min-1 100 g tissue-1), P<0.001. Likewise, the changes in signal inten-sity as a measure of the microvascular volume increased significantly 1-h after infusion of GIP and the clamp (P=0.003). During infusion of saline and the clamp, both ATBF (2.8 ± 0.8 ml min-1 100 g tissue-1) and microvascular volume remained unchanged throughout the experiments (P=NS).

Conclusion: The increase in ATBF during GIP infusion involves recruitment of capillaries in healthy lean subjects.

A537


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



ing a hypoglycaemic clamp and healthy volunteers using different collection tubes (Becton, Dickinson and Company Vacutainer System, Franklin Lakes, NJ): K3EDTA tube, EDTA aprotinin tube, P800 tube). Samples were used to investigate the performance of the glucagon assay, to evaluate glucagon recovery and to investigate long-term glucagon stability in different storage vials (Sorenson Twist Top, Rotilab glass, Greiner plastic, Eppendorf Protein LoBind) including freeze/thaw stability. P800 tubes prevented glucagon deg-radation up to 6 hrs even at room temperature (RT) showing a recovery of 102%. Adding aprotinin did not have a positive effect on enzymatic degra-dation. After 6 hrs at RT samples collected in EDTA aprotinin tubes had a recovery of only 50%. Glucagon recovery in K3EDTA tubes was as low as 33%. Sorenson Twist Top vials showed the lowest glucagon recovery while all other vials had similar concentrations. Glucagon concentrations remained unchanged for up to 15 month at ≤-70°C without freeze/thaw cycles. After two freeze/thaw cycles glucagon recovery ranged from 97%-103%. After three additional freeze/thaw cycles glucagon recovery decreased to 70%-79%. We conclude that glucagon is stable for at least 15 months without any freeze/thaw cycles when using adequate sampling and storage material which is relevant in clinical settings where samples cannot be immediately processed.

2039‑PFNDC4 Promotes Brown‑Like Adipocyte Formation and Glucose Clearance via an Orphan G‑protein Coupled ReceptorXIAOCHUAN MA, MADELEEN BOSMA, OLGA SHILKOVA, MAUDE GIROUD, JUAN C. HIGAREDA-ALMARAZ, VENETIA BAZIOTI, TILO WUENSCH, MALIN ELVEN, STEVEN SEAMAN, OLLI RITVOS, NOBUHIRO NAKAMURA, SHIGEHISA HIROSE, MARTIN IRMLER, JOHANNES BECKERS, ROBERT JANOWSKI, DIERK NIESSING, BRAD S.T. CROIX, TARJA NIEMI, MARKKU TAITTONEN, PIRJO NUUTILA, KIRSI A. VIRTANEN, MARTIN WABITSCH, ARNE DIETRICH, MATTHIAS BLÜHER, MARCEL SCHEIDELER, STEPHAN HERZIG, ANASTASIA GEORGIADI, Stockholm, Sweden, Munich, Germany, Frederick, MD, Helsinki, Finland, Yokohama, Japan, Turku, Finland, Ulm, Germany, Leipzig, Germany

Hormonal induction of brown-like adipocyte formation within the white adipose tissue holds a promising therapeutic approach to treat type 2 dia-betes. Fibronectin type III domain containing 4 (FNDC4) is a type I mem-brane protein, which is cleaved to release a soluble peptide, which is 100% homologous between human and mouse. Recently, we have published the benefits of injectable FNDC4 in the treatment of inflammatory bowel dis-ease. In the present research we aim to investigate the metabolic aspects of FNDC4. FNDC4 is most highly expressed in the brain and liver in both human and mice. We interrogated the relevance of FNDC4 in humans and we found in a small cohort of lean, nondiabetic individuals, that higher liver mRNA levels of FNDC4 correlated with better glucose tolerance and lower blood glucose levels at fasting. Soluble FNDC4 fused to hIgG (FcFNDC4) increased UCP1 mRNA and protein levels in both, human multipotent adipose-derived stem (hMADS) cell derived adipocytes and primary human subcutaneous adipocytes from healthy individuals, and induced cAMP and ERK1/2 signal-ling in mouse adipocytes. Adenoviral over expression of full length FNDC4 or intra peritoneal injections of FcFNDC4 improved glucose clearance in mice. To further elucidate the mechanism of action of FNDC4, we screened for candidate receptors. We identified the orphan Adhesion G Protein-Coupled Receptor F5 as a candidate. Over expression of this receptor in mouse white adipocytes resulted in formation of brown-like adipocytes, while whole body deletion in mice resulted in severe glucose intolerance and prevented the activation of FNDC4 signalling in the white fat. Furthermore, we found hepatic FNDC4 mRNA levels to be reduced to 50% in mouse models of obe-sity and diabetics, as well as in humans (obese and type 2 diabetics). Overall our study presents a novel mechanism for future therapeutic applications against type 2 diabetes.

Supported By: European Research Council; Vetenskapsrådet; Stiftelsen för strat-egisk Forskning; Ragnar Söderbergs Stiftelse; European Foundation for the Study of Diabetes; Wenner-Gren Stiftelsen; Diabetes fonden och Svenska Sällskapet för Medicinsk Forskning; Netherlands Organisation for Scientific Research (to A.G.); European Union (HEALTH-F2-2011-278373 to P.N., K.A.V., M.S., S.H.)

2040‑PGlucagon Receptor Signaling at the Adipocyte Inhibits LipolysisJENNIFER H. STERN, DANIEL J. DRUCKER, PHILIPP E. SCHERER, Dallas, TX, Toronto, ON, Canada

Inhibition of glucagon receptor signaling improves glucose homeostasis in type 2 diabetes. The therapeutic benefit of glucagon receptor inhibi-tion is mainly attributed to a decrease in hepatic glucose output, yet our studies demonstrate that the adipocyte is an important site of glucagon

to cold exposure. Therefore, we hypothesised that FGF-21 may mediate and is required for the effect of Isoproterenol (Iso) treatment on adipocytes.

Methods: The effect of Iso on FGF-21 gene expression and secretion were studied in three different adipocyte cell lines (3T3-L1, ME3 and WT-1). The metabolic response to Iso and FGF-21 was investigated by measuring the thermogenic gene regulation, lactate production, glucose uptake and lipoly-sis. To investigate FGF-21’s autocrine role after β-adrenergic stimulation the metabolic regulation in response to Iso was studied in the absence or pres-ence of PD173074, a FGF receptor inhibitor.

Results: All three adipocyte cell lines (3T3-L1, ME3, WT-1) expressed the FGF-21 receptor complex (FGF-R1 and β-klotho), β3-adrenergic receptors and various degrees of UCP1. The WT-1 adipocytes had the highest expression of UCP1 while the lowest expression was found in 3T3-L1 adipocytes. In response to Iso, FGF-21 gene expression was increased in WT-1 and ME3, but decreased in 3T3-L1 adipocytes after 24 hours of incubation with Iso. However, FGF-21 secretion in the medium was increased in all three cell types in response to Iso. Glucose uptake, lactate production and lipolysis were induced to various degrees in response to Iso and FGF-21 as well as the gene expression of UCP1. FGF-21 and Iso showed no synergistic effect (no change in EC50) on glucose uptake. When the FGF receptor inhibitor PD173074 was present during stimulation with Iso the glucose uptake was partly reduced in all three cell lines indicating that FGF-21 has an autocrine role after β-adrenergic stimulation. Therefore, FGF-21 may be required for the thermogenic adaptation to cold exposure in mice and humans.

2037‑PAssociation of Plasma Relaxin Levels with Markers of Metabolic and Cardiac Function in Patients with DiabetesROBERT G. BENNETT, FREDERICK G. HAMEL, RONDA L. SIMPSON, CYRUS V. DESOUZA, Omaha, NE

Relaxin is a polypeptide hormone normally detectable in the blood only during the first trimester of pregnancy, although it can be produced by the failing heart. Little is known about the levels of circulating relaxin in patients with type 2 diabetes. We enrolled 99 patients, including 50 patients without type 2 diabetes and 49 patients with type 2 diabetes. Serum panels and body mass analysis were performed, and plasma relaxin was determined using a validated assay. As expected, relaxin was below the limit of detec-tion in most patients, with more relaxin-positive patients with diabetes than without (35% vs. 22%, respectively). In patients with diabetes, relaxin cor-related positively with high density cholesterol (HDL), and negatively with hemoglobin A1c (HbA1c), and approached statistical significance with other determinants (Table), but not weight, age or BMI. Relaxin also correlated with brain natriuretic peptide levels in patients with a history of congestive heart failure (n=24).

In summary, relaxin correlated positively with beneficial markers of dia-betes (higher HDL, lower HbA1c) in patients with diabetes, suggesting that relaxin levels may be differentially regulated in patients with more effective glucose control. Secondly, relaxin correlated with BNP levels, providing fur-ther evidence that it may be a viable blood marker for heart disease.

Table. Spearman Correlations of Relaxin with Selected Determinants.Spearman coefficient (r) p value

HbA1c -0.296 0.04*Fasting glucose -0.257 0.07Fat mass -0.274 0.06C-reactive protein -0.274 0.06HDL 0.304 0.03*BNP 0.425 0.04*

2038‑PLatest News on Glucagon StabilityMARTINA BRUNNER, REINGARD RAML, SELMA MAUTNER, SABINE ZENZ, ROB-ERT LIPP, THOMAS PIEBER, Graz, Austria

Numerous studies have focused on the physiological and pathophysi-ological role of glucagon but mechanisms of glucagon secretion still remain unclear aggravated by a lack of highly accurate methods for glucagon mea-surement. Recently, a highly specific sandwich ELISA (Mercodia) has become available but since immunoreactive glucagon is susceptible to proteolytic degradation after blood collection, preanalytical sampling and storage can have a major effect on analytical results. This study aimed to determine the effect of different sampling materials and various storage conditions on glu-cagon recovery. Blood was collected from patients with type 1 diabetes dur-

A538


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS



placed in the femoral artery and in the hepatic and femoral veins. Continuous oral feeding with a liquid meal (50% carbohydrate, 35% fat, 15% protein) was initiated and continued for 8.5 h to establish steady-state meal absorp-tion and insulin-mediated suppression of lipolysis in VF. Systemic (SYST) and splanchnic (SPL) oleate (OL) rate of appearance (Ra) and fractional spillover (SO) of lipoprotein lipase-generated fatty acids from circulating triglycerides (a reflection of the efficiency of dietary fat storage) were determined during meal absorption with infusions of [U-13C] OL and [3H] triolein. During feeding, insulin concentrations increased from baseline values of 11±1 μU/ml to 36±4 μU/ml. SYST and SPL OL Ra were 80±7 and 49±6 μmol/min, respectively; The SPL bed was responsible for 64±6% of SYST OL Ra. SPL SO was greater than SYST SO (83±6% vs. 32±3%, p<0.0001). VF was 224±30 cm3. There was no correlation between VF and SYST OL Ra (R = 0.31, p=NS). However, there was a positive association between the size of the VF depot and SPL OL Ra (R = 0.66, p = 0.02). SPL OL Ra also correlated with SPL SO (R = 0.75, p = 0.007).

In summary, in overweight and obese people with dyslipidemia, the major-ity of circulating free fatty acids during meal absorption derive from SPL lipolysis, which occurs primarily in VF. Rates of SPL lipolysis are increased in relation to the size of the VF depot. Further, SO in VF appears to be coupled to intracellular lipolysis, such that there is increasing inefficiency in dietary fat storage as lipolysis increases. Resistance to the antilipolytic effects of insulin in VF may play an important role in the pathogenesis of dyslipidemia.

Supported By: National Institutes of Health (HL67933, DK29953)

2043‑PGhrelin Suppresses Insulin Secretion More Potently under Low Glu‑cose than High Glucose in RodentsJINGJING NIU, JONATHAN CAMPBELL, DAVID A. D’ALESSIO, JENNY TONG, Durham, NC

Ghrelin inhibits glucose-stimulated insulin secretion (GSIS) in rodents and healthy humans, and recent studies suggest that this may be mediated by delta-cell somatostatin. In mice with severe caloric restriction, ghrelin is necessary to prevent hypoglycemia and maintain survival, but its effect on insulin secretion in this setting is not clear. To gain insight into the effects of ghrelin during starvation we compared the effect on insulin secretion in isolated islets under low and high glucose concentrations. Pancreatic islets were isolated from C56BL6J mice (n = 6) and perifused with 10 nM and 100 nM of acyl ghrelin under low (2.7 mM) and high (16.7 mM) glucose conditions. During low glucose perifusion, insulin secretion was suppressed by 61.6% (0.256 ± 0.003 to 0.0984 ± 0.004 ng/ml, mean ± SEM) and 59.2% (0.255 ± 0.005 to 0.104 ± 0.005 ng/ml) in response to 10 mM and 100 mM treatment with acyl ghrelin. Ghrelin suppression of insulin release was lower during exposure to 16.7 mM glucose, 11.3% (0.504 ± 0.013 to 0.447 ± 0.011 ng/ml) with 10 nM, and 29.1% (0.596 ± 0.025 to 0.423 ± 0.014 ng/ml) with 100 nM, ghrelin. However, there was an immediate and robust increase of GSIS 4 min the ghrelin infusion was stopped, suggesting disinhibition of β-cells. These findings indicate that ghrelin suppresses GSIS more potently under low glu-cose than high glucose conditions. This is consistent with a role defending against hypoglycemia during caloric restriction.

Supported By: National Institutes of Health (5R01DK097550)

2044‑PFAHFAs, Novel Antidiabetic Lipids, in Subjects with Obesity and Type 2 Diabetes Mellitus: The Influence of Metabolic SurgeryMILOS MRAZ, JANA KLOUCKOVA, PETRA KAVALKOVA, ANNA CINKAJZLOVA, HELENA KRATOCHVILOVA, ZDENKA LACINOVA, KARIN DOLEZALOVA, MARTIN FRIED, PETR KACER, MARTIN HALUZIK, Prague, Czech Republic

Fatty acid esters of hydroxy fatty acids (FAHFAs) are a novel class of lipids with beneficial metabolic and antiinflammatory effects. The aim of our study was to assess the effect of metabolic surgery on serum levels of FAHFAs in subjects with obesity and type 2 diabetes mellitus (T2DM). Eleven obese subjects without T2DM (OB group, aged 47.6 ± 9.1 years) and 11 obese T2DM subjects (DM group, aged 54.6 ± 8.4 years) were examined before and 1, 6 and 12 months after surgery. Serum levels of PAHSA (palmytic acid ester of hydroxystearic acid), POHSA (palmytoleic acid ester of hydroxystearic acid) and OAHSA (oleic ester of hydroxystearic acid) were measured using LC-MS (liquid chromatography-mass spectrometry). In both groups metabolic sur-gery reduced body weight (BMI 43.0 ± 7.4 vs. 37.9 ± 7.9 kg/m2 for baseline vs. 12 months, p<0.001 for OB and 40.8 ± 5.8 vs. 36.6 ± 5.6 kg/m2, p<0.001 for DM), improved glucose control (HbA1c 37.8 ± 4.7 vs. 34.3 ± 4.4 mmol/mol, p=0.007 for OB and 64.8 ± 17.4 vs. 56.5 ± 16.2 mmol/mol, p=0.004 for DM) and decreased systemic inflammation (hsCRP 4.7 ± 4.7 vs. 1.9 ± 2.0 mg/l, p<0.001 for OB and 3.9 ± 2.8 vs. 1.2 ± 1.3 mg/l, p<0.001 for DM). All FAHFAs markedly increased already 1 month after surgery with a subsequent partial

action. Despite maintaining similar body weight, adipocyte-specific gluca-gon receptor deletion (GcgrAdipocyte-/-) elevates circulating glucagon (P≤0.01). Thus, glucagon signaling at the adipocyte may feedback to limit α-cell glu-cagon release. Furthermore, adipocyte-specific glucagon receptor deletion improves glucose tolerance in lean and diet-induced obese mice, despite increasing serum glucagon (P≤0.01). Our adipocyte specific knockout model is ideal for assessing the role of glucagon in adipose tissue lipolysis. As a fasting hormone, we expect glucagon would act to induce adipose tissue lipolysis. Yet our studies show that glucagon inhibits adipose tissue lipoly-sis. In fact, intraperitoneal glucagon administration (5 μg/kg body weight) decreases circulating non-esterified fatty acids in fasted mice (P≤0.01). To isolate the response in adipose tissue, we established that glucagon inhibits ex vivo adipose tissue lipolysis (P≤0.001). Consistent with these observa-tions, lipolysis is significantly elevated in explants from adipocyte-specific glucagon receptor knockout mice (P≤0.05). Increasing lipolysis results in ectopic lipid accumulation. Accordingly, our studies show that both lean and diet-induced obese GcgrAdipocyte-/- mice have increased hepatic lipid accumulation (P≤0.05). Together, our data suggests that, despite improve-ments in glucose clearance, inhibition of glucagon signaling at the adipocyte increases adipose tissue lipolysis, leading to ectopic lipid accumulation, a risk factor for metabolic diseases.


2041‑PSupporting NOS Activity Restores Vascular Reactivity and Improves Insulin‑Stimulated Glucose Uptake in Sedentary Wistar RatsAMY C. KELLER, LESLIE A. KNAUB, REBECCA L. SCALZO, LORI A. WALKER, JANE E.B. REUSCH, Aurora, CO, Denver, CO

Sedentary behavior is a risk factor for cardiovascular disease. Endothelial nitric oxide synthase (eNOS) regulates vascular reactivity and, in part, vascu-lar mitochondria function. Work in our lab has demonstrated that sedentary rats develop impaired endothelium dependent vasorelaxation between ages 10 and 20 weeks; this impairment may be secondary to sedentary-induced eNOS dysfunction. We hypothesized that supporting eNOS function with sepiapterin, a precursor to the eNOS cofactor BH4, in sedentary rats would result in improved vascular contractility and vascular mitochondrial func-tion. Sedentary Wistar rats (n=9, 8-10 weeks old) ate a customized diet ad libitum for a total of 10 weeks. Sepiapterin was administered in diet during the final 5 weeks (n=4). Intraperitoneal insulin tolerance tests (IP-ITT) were conducted at baseline and endpoint. Rats were sacrificed at 18-20 weeks. Aorta was assessed for mitochondrial respiration and contractile response. As expected, vasorelaxation with acetylcholine significantly improved in aorta from sepiapterin treated rats (p<0.05 for all). Rats fed sepiapterin had elevated state 3 and 4 aortic mitochondrial respiration (p<0.05). Insulin toler-ance, determined by the cumulative glucose response to the IP-ITT, improved in rats fed sepiapterin (control DAUC: 801.0 ± 265.4 vs. sepiapterin DAUC: -645.9 ± 469.0; p<0.05). Further, the glucose concentration was lower 60 minutes after insulin injection in the sepiapterin fed rats at the end of the study (time x treatment interaction; p<0.05).

In summary, targeting eNOS in sedentary rats increased vascular function and vascular mitochondrial respiration. In addition, sepiapterin improved glucose uptake in the presence of insulin. The metabolic improvements in sepiapterin fed rats may be due to eNOS-mediated correction of excess reactive oxygen species, increase of muscle perfusion, or modulation of cel-lular signaling regulating insulin sensitivity.

Supported By: National Institute on Aging/National Institutes of Health (R01AG027678, K01AG20683, R56HL114073); National Institutes of Health/National Center for Research Resources-Colorado Center for Translational Science Insti-tute (UL1RR025780); University of Colorado Denver Center for Women’s Health Research; National Institutes of Health (T32HL007171-36, 5P01HL014985); Astra-Zeneca; U.S. Department of Veterans Affairs; Denver Research Institute; Colorado Nutrition Obesity Research Center (P30DK048520)

2042‑PRegulation of Dietary Fat Storage and Lipolysis in Visceral Fat of Dyslipidemic SubjectsJOHN M. MILES, KELLY T. DUNAGAN, ALMIRA SMAILOVIC, JENNIFER ISAUTIER, BARBARA J. NORBY, MICHAEL A. MCKUSICK, EKTA KAPOOR, VINAYA SIMHA, RITA BASU, Kansas City, KS, Rochester, MN

The regulation of fat storage and lipolysis in visceral fat (VF), which is associated with insulin resistance, is not well understood. VF was measured with single-slice CT in overweight and obese nondiabetic subjects with dys-lipidemia (n=12, age 51±3 y, BMI 31±1 kg/m2, triglycerides 265±40 mg/dl, HDL chol 37±2 mg/dl). After an overnight fast, blood sampling catheters were

A539


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—ANIMAL

composition analysis indicated an increase in fat mass rather than lean mass increased in Nrf2CNSD mice with reduced O2 consumption and CO2 produc-tion. Consistent with these responses, Nrf2CNSD mice had increased induced insulin resistance as measured by ITT and abnormal IPGTT responses. No significant change in blood pressure was observed between Nrf2CNSD and wild type controls.

Conclusions: These results indicate that anti-oxidant responses in key cir-cumventricular organs of the central nervous system plays an important role in the genesis of obesity and obesity-induced insulin resistance.

Supported By: Poxel SA

& 2047‑PA Novel GLP‑1 Positive Allosteric Modulator, INO352, Suppresses Blood Glucose Excursion after Food Intake in Obese Type 2 Diabetic MiceYOSHIRO KITAHARA, TOMOHIRO FUJII, YORIKO OKAMATSU, KOJI OHSUMI, Kawasaki, Japan

GLP-1 is an incretin hormone that not only plays an important role in glucose metabolism, but also in the regulation of satiety, gastrointestinal function, and cardiovascular function. In addition, the GLP-1 receptor is also expressed by intestinal intra-epithelial lymphocytes and is involved in regulating innate immunity and gut microbiota. Thus, the GLP-1 receptor is thought to be a promising target for treatment of metabolic syndrome. Since GLP-1 secretion after food intake is reported to be attenuated in patients with obesity and/or type 2 diabetes, sensitization of the GLP-1 receptor to GLP-1 could be another effective therapeutic option. Therefore, we devel-oped novel positive allosteric modulators (PAMs) of the GLP-1 receptor. Using human GLP-1 receptor-expressing HEK293 cells, we identified several PAMs with EC50 values<2 μM by random screening of our chemical library. After optimization of these compounds, we obtained highly potent com-pounds (EC50<10 nM). INO352 is one of these potent compounds (EC50=6.7 nM), and it potentiated the effect of GLP-1 on GLP-1 receptor-expressing HEK293 cells by 6.5-fold. INO352 augmented insulin secretion by isolated rat pancreatic islets in response to 1 nM exendin-4 and high glucose (8.3 mM), while it had no effect in the absence of exendin-4. Next, the hypogly-cemic activity of this compound was investigated in obese type 2 diabetic KKAy mice. After an overnight fast, mice were administered 3 g/kg of whey protein to induce GLP-1 secretion. At 30 minutes after whey protein, INO352 (3 mg/kg) and a liquid meal (8.7 kcal/kg) were administered, and the blood glucose level was monitored. INO352 significantly reduced the glucose area under the curve after administration of the liquid meal. These results indi-cate that INO352 potentiates GLP-1 activity in response to food intake and regulates postprandial glucose metabolism. Therefore, GLP-1 receptor PAMs may be an attractive alternative to incretin-based therapy.

& 2048‑PDeficiency of Absent in Melanoma (AIM) 2, a Tumor Suppressor Gene, Induces Spontaneous Obesity and Hyperglycemia in MiceZHENWEI GONG, KAI SU, JIERU WANG, RADHIKA MUZUMDAR, Pittsburgh, PA

Aim2 is an inflammasomal protein and cytosolic sensor for double-stranded DNA (dsDNA). Its independent role in tumor suppression has been discovered in melanoma, colorectal cancer, breast cancer, liver cancer and prostate cancer. Here, we report that mice with whole body deletion of Aim2 (Aim2-/-) exhibit increased body weight, total fat mass (without change in lean mass), visceral and subcutaneous adiposity without significant changes in food intake. Increased adiposity in Aim2-/- mice is attributable to the ele-vated adipogenesis; gene expression and protein levels of pro-adipogenic genes such as peroxisome proliferator-activated receptor gamma (PPAR-gamma), CCAAT-enhancer-binding proteins (C/EBP) -beta and -alpha and target genes are dramatically increased in white adipose tissue (WAT) of Aim2-/- mice. Primary fibroblasts isolated from WAT of Aim2 -/- mice exhibit significantly high adipocyte differentiation capability compared to those from wild type mice, while over-expression of Aim2 in 3T3-L1 preadipocytes significantly inhibits adipocyte differentiation. RNA-sequencing revealed increased expression of interferon activated gene (Ifi) 202b, a pro-adiopo-genic gene in Aim2-/- mice; increased Ifi202b mRNA expression and protein levels were confirmed in WAT in Aim2-/- mice by real time PCR and immunob-lot respectively. Consistent with the increased visceral adiposity, Aim2-/- mice demonstrate fasting hyperglycemia and glucose intolerance, indicating impaired glucose homeostasis in these mice. Taken together, our data shows that Aim2 is a novel regulator of adipogenesis and glucose homeostasis.

Supported By: National Institutes of Health; Children’s Hospital of Pittsburgh Foundation

decrease (PAHSA 30.6 ± 2.7 vs. 91.5 ± 3.9 vs. 65.1 ± 3.9 pg/ml, p<0.05 for OB and 22.5 ± 6.0 vs. 195.4 ± 25.8 vs. 128.4 ± 13.9 pg/ml, p<0.05 for DM; POHSA 26.8 ± 3.7 vs. 80.1 ± 11.3 vs. 60.1 ± 7.4 pg/ml, p<0.05 for OB and 27.5 ± 7.1 vs. 235.5 ± 27.4 vs. 146.2 ± 19.7 pg/ml, p<0.05 for DM; OAHSA 16.5 ± 3.3 vs. 122.4 ± 16.0 vs. 70.9 ± 12.2 pg/ml, p<0.05 for OB and 15.5 ± 1.5 vs. 178.1 ± 15.6 vs. 108.6 ± 6.6 pg/ml, p<0.05 for DM). Interestingly, despite comparable baseline values all FAHFAs reached significantly higher postsurgical levels in DM compared with OB subjects.

To conclude, metabolic surgery is associated with a rapid increase in serum FAHFAs in obese subjects that is further potentiated by the presence of T2DM. These changes might contribute to positive metabolic effect of bariatric procedures.

Supported By: Ministry of Health of the Czech Republic (VFN64165); Institute for Clinical and Experimental Medicine (IN000023001, 15-26854A)

2045‑P

OBESITY—ANIMAL

Moderated Poster Discussion: Mouse Models of Diabesity—Central and Peripheral Mechanisms (Posters: 2046-P to 2051-P), see page 16.

& 2046‑PCentral Nrf2 Antioxidant Response Protects Mice from Obesity‑Induced Insulin ResistanceXIAOQUAN RAO, JIXIN ZHONG, THOMAS SUSSAN, SHYAM S. BISWAL, SANJAY RAJAGOPALAN, Cleveland, OH, Baltimore, MD

Background: Obesity is a major risk factor for insulin resistance and dia-betes. However, the underlying mechanisms are not fully understood. In this study, we investigated the role of central nervous system Nrf2 anti-oxidant response in the development of obesity-induced insulin resistance and glu-cose intolerance.

Methods: Twelve week-old male Nrf2fl/fl mice were injected intracere-broventricularly (ICV) with Cre-expressing adeno-associated virus (AAV) to induce central deficiency of Nrf2 (Nrf2CNSD). Mice injected with GFP-express-ing AAV served as controls. Four weeks after AAV infection, mice were fed a high fat diet (60% energy from fat) for 12 weeks. Metabolism was assessed using a Comprehensive Lab Animal Monitoring (CLAMS) System, body com-position was evaluated using magnetic resonance imaging. Blood pressure, insulin sensitivity and post-prandial responses were assessed.

Results: After high fat diet feeding Nrf2CNSD mice gained more weight compared to corresponding controls with a increase in food intake. Body

WITHDRAWN

A540


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—ANIMAL

& 2051‑PSmall Proliferative Adipocytes, Newly Identified Adipocyte Pro‑genitor, Differentiate into Mature Adipocyte EfficientlyKOICHIRO TAGUCHI, KAZUO KAJITA, YOSHIHIKO KITADA, MASAYUKI FUWA, MASAHIRO YAMAUCHI, TAKAHIDE IKEDA, TATSUO ISHIZUKA, HIROYUKI MORITA, Gifu, Japan

We previously identified proliferative cells in adipose tissue expressing adipocyte specific genes. Since adipocyte specific genes are considered to emerge after the growth arrest of adipocyte progenitor, we named these cells small proliferative adipocytes (SPA). In this study, we investigated the gene expression in SPA and their ability of differentiation by comparing them with stromal vascular cells (SVC) and mature adipocytes (MA). Microarrays and real time PCR analyses revealed that the expression of adipocyte spe-cific genes, including PPARγ2, adiponectin and leptin was increased in the order of SVC < SPA << MA. Genes involved in fatty acid synthesis, sterol regulatory element binding protein-1 and fatty acid synthase, were detected in MA. Several neuronal genes, such as glutamate receptor 7 (Grm7), and synuclein γ, were increased in the order of SVC < SPA < MA. On the other hand, proliferin 2 (PLF2) was detected only in SPA. Therefore, PLF could be regarded as a marker of SPA. Immunohistochemical studies confirmed these results. Interestingly, adiponectin, Grm7 and PLF were detected in lipoma, while only PLF in liposarcoma. Adipogenic differentiation was induced with insulin/dexamethasone/IBMX in SPA and SVC. However, SPA was superior to SVC for the induced expression level of adipocyte specific genes and lipid accumulation. Moreover, treatment with pioglitazone promoted lipid accu-mulation in SPA, but not SVC. These data indicate that SPA are more suitable as a candidate for adipocyte progenitor than SVC. In addition, lipoma and liposarcoma might consist mainly of transformed SPA.

2052‑PThe Transcriptional Coactivator NT‑PGC‑1α Localizes to Mitochon‑dria and Regulates Mitochondrial DNA‑Encoded Gene Expression in Brown AdipocytesJI SUK CHANG, KYOUNGSOO HA, Baton Rouge, LA

Transcriptional coactivators, PGC-1α and NT-PGC-1α, play important roles in cold-induced brown adipose tissue thermogenesis by regulating the expression of thermogenic and mitochondrial genes in the nucleus. Here, we provide the first evidence that a portion of NT-PGC-1α localizes to brown adipocyte mitochondria. Biochemical, immunocytochemical and immunoelectron microscopic analyses demonstrated that NT-PGC-1α was targeted to the mitochondrial matrix in brown adipocytes and enriched at the D-loop region of the mitochondrial DNA (mtDNA) that encodes several essential subunits of the electron transport chain (ETC) complexes. Expres-sion of NT-PGC-1α and PGC-1α in PGC-1α-/- brown adipocytes led to a com-parable increase in nuclear DNA-encoded mitochondrial gene expression. In contrast, mtDNA-endcoded ETC gene expression was significantly higher in NT-PGC-1α-expressing brown adipocytes than in PGC-1α-expressing brown adipocytes. Moreover, NT-PGC-1α-expressing brown adipocytes had higher mitochondrial respiration rates compared with PGC-1α-expressing brown adipocytes. A targeted protein expression strategy using a mitochondrial localization signal (MLS) further demonstrated that expression of MLS-NT-PGC-1α in PGC-1α-/- brown adipocytes led to enhanced mtDNA encoded gene expression and mitochondrial respiration. Collectively, we have identi-fied a previously unappreciated and isoform-specific role for NT-PGC-1α in the regulation of mtDNA transcription in brown adipocytes, providing new insight into the transcriptional control of mitochondrial respiratory function.


2053‑PHigh‑Intensity Interval but Not Endurance Training Reverses Meta‑bolic and Muscle Disturbances in Obese MiceSERGIO F. MARTINEZ HUENCHULLAN, LUISA OLAYA-AGUDO, CHARMAINE S. TAM, SUSAN V. MCLENNAN, STEPHEN M. TWIGG, Sydney, Australia

Obesity is related to the development of skeletal muscle dysfunction, changing its extracellular matrix (ECM) composition. To determine if exer-cise is capable of reversing these changes, we investigated the effect of two isocaloric exercise programs; moderate endurance (END) or high intensity interval training (HIIT), in a mouse model of diet-induced obesity. Ten week-old male C57BL/6 mice were fed a high fat diet (HFD; 45% kcal fat) ab libitum for 10 weeks to 25% excess weight, then for a further 10 weeks when they underwent END or HIIT (3x40 min sessions/week). Untrained HFD and chow-fed mice were controls. After 20 weeks mice were sacrificed and the quad-riceps muscle was removed for analysis. END and HIIT did not change the

& 2049‑PATPIF1 Knockout (KO) Mice Are Protected from Diet‑Induced Obe‑sity (DIO) and Glucose IntoleranceBRYDIE R. HUCKESTEIN, LIA R. EDMUNDS, YINGZE ZHANG, YANXIA CHU, MICHAEL J. JURCZAK, Pittsburgh, PA

The etiology of obesity is complex and likely influenced by factors other than overfeeding and reduced activity. Differences in energy efficiency may be one such factor and could provide a novel mechanism for treating obe-sity. ATPase inhibitory factor 1 (ATPIF1) inhibits the ATPase activity of ATP synthase such that inhibition of ATPIF1 may reduce mitochondrial efficiency by promoting ATP consumption and proton transport against a concentration gradient by ATP synthase. To determine how ATPIF1 loss impacts energy balance in vivo, we studied WT and ATPIF1 KO mice fed regular chow (RC) or high-fat diet (HFD; 60% kcal fat) for ~10 weeks. There were no differ-ences in body weight (BW), fat or lean mass between RC groups. In contrast, HFD caused a significant (P<0.001) 40% increase in BW in WT, but only a 20% non-significant increase in KO mice. HFD WT weighed 25% more than KO mice (P<0.01), which was accounted for by increased adiposity (P<0.01) and no change in lean mass. Preliminary metabolic cage studies (n=4/group) detected no significant differences in energy expenditure, activity or feeding that accounted for protection from DIO. Plasma leptin was 50% less in HFD KO compared with WT mice and plasma resistin was similarly 45% less. Six-hour fasted plasma glucose and insulin did not differ between HFD groups, but KO mice displayed significantly reduced plasma glucose during glucose tolerance test (GTT) (P<0.05 t=30-120 min) and glucose AUC was 15% less (P<0.05). Insulin levels during GTT were qualitatively different between groups. Glucose dosing had no effect on insulin in WT, but caused a two-fold increase in insulin in KO mice from zero to 15 min that returned to 40% of baseline by 120 min. Ectopic lipid is associated with insulin resistance, but there were no differences in triglyceride content in skeletal muscle from HFD WT and KO mice. Future studies to determine how ATIPF1 deletion affects mitochondrial bioenergetics and the mechanism(s) for protection from DIO and improved GTT are of great interest.

& 2050‑PPBI‑4050 Improves Glucose Metabolism and Insulin Resistance, and Reduces Liver Damage in a High‑Fat Diet Mouse Model of Obe‑sity and Metabolic SyndromeBRIGITTE GROUIX, MIKAËL TREMBLAY, LIETTE GERVAIS, FRANÇOIS SARRA-BOURNET, ALEXANDRA FELTON, PIERRE LAURIN, LYNE GAGNON, Laval, QC, Canada

Introduction and Aims: Obesity and its resulting metabolic disturbances are major health threats and are the main cause of a host of diseases, including nonalcoholic fatty liver disease (NAFLD). PBI-4050, a novel first-in-class orally active compound, is currently in clinical phase II in diabetic patients with metabolic syndrome. The aim of this study was to investigate the effects of PBI-4050 in a mouse model of high-fat diet-induced obesity and metabolic syndrome.

Methods: C57BL/6 mice were fed with either a standard or a high-fat diet (HFD, Harlan, TD.06414) for 14 weeks. These mice were divided in three groups [Normal chow, HFD + Vehicle, and HFD + PBI-4050 (200 mg/kg, oral once a day)] and treated for an additional 6 weeks. Blood biochemistry, serum insulin level, liver histology, as well as liver and white adipose tissue (WAT) pro-inflammatory/fibrotic gene expression were examined.

Results: In oral glucose tolerance test, PBI-4050 increased glucose metab-olism compared to the HFD control group. Insulin resistance (measured by HOMA-IR) and β cell function (HOMA1-β) were improved by PBI-4050. Serum triglyceride level was significantly reduced by PBI-4050. Histology analysis showed a significant reduction of hepatic steatosis and ballooning by PBI-4050. To further characterize the activity of PBI-4050, quantitative RT-PCR analysis of profibrotic markers was performed, demonstrating that PBI-4050 reduced collagen types I and III, CTGF, MMP-2, and TIMP-1 gene expression in the liver, as well as MCP-1, MMP-2 and collagen type I gene expression in the WAT. Moreover, adiponectin gene expression which was downregulated in WAT of the HFD control group was significantly increased by PBI-4050.

Conclusions: Taken together, these results suggest that PBI-4050 offers the potential as a novel therapy for nonalcoholic fatty liver disease, obesity and diabetes associated with metabolic syndrome.

A541


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—ANIMAL

whole-mount immunofluorescence study of organ cultured eWAT. Treatment of the tissues with PDGF-B or SDF1 alone for 24 hrs significantly promoted detachment of PCs from vessels, and these effects on PCs were blunted by deletion of PDGFRB or preincubation of AMD3100, a SDF1 receptor antago-nist. Interestingly, associations of PCs with vessels were preserved in cul-tured eWAT treated with both PDGF-B and SDF1. Therefore, the cell-type- and location-specific expressions of these factors appear to be important for their regulation of PCs. To further clarify the in vivo effect of SDF1 in adipose tissue during obesity, we administrated Anagliptin (Ana), a DPP-4 inhibitor to C57BL/6J mice fed chow or high fat diet (HFD) for 12 weeks, since SDF1 is the known substrate for DPP-4. Treatment with Ana significantly ameliorated HFD-induced glucose intolerance and insulin resistance. Impor-tantly, HFD-induced adipose tissue expansion was significantly attenuated by treatment with Ana. In addition, vascular density was decreased, and HFD-induced PCs detachment from vessels was attenuated in the eWAT of Ana-treated mice. These findings suggest that both PDGF-B and SDF1 are proangiogenic factors coordinately regulating PCs detachments and adipose tissue expansion in mice.

2056‑PDissecting the Roles of High‑Fat Diet and Hyperleptinemia in the Development of Leptin ResistanceMICHELLE M. KWON, JULIA N.C. TOEWS, ROBERT K. BAKER, TIMOTHY J. KIEFFER, Vancouver, BC, Canada

High fat diet (HFD) feeding and hyperleptinemia are thought to cause leptin resistance but their contributions are difficult to dissect since HFD feeding and hyperleptinemia are linked. To test the contribution of HFD to leptin resistance, we administered a vehicle or plasmid encoding leptin by hydrodynamic delivery to streptozotocin (STZ) diabetic mice. Follow-ing the normalization of blood glucose levels with leptin (24.9±1.0 and 5.8±1.4 mM on days -1 and 6), we fed the mice HFD. Despite maintenance of hyperleptinemia (303±37 and 319±44 ng/ml on days 6 and 12), HFD fed mice rapidly developed resistance to the blood glucose lowering actions of leptin (19.2±2.2 mM on day 10) and leptin remained inefficacious long term. Next, we fed new mice a HFD for 12 weeks, which led to hyperlepti-nemia (115±7 ng/ml), injected STZ to induce diabetes, then delivered con-trol or leptin plasmids. Despite hyperleptinemia (205±38 ng/ml on day 19), leptin did not lower blood glucose levels compared to controls (25.6±0.9 and 21.8±1.5 mM on day 19). To test the contribution of hyperleptinemia to leptin resistance, we injected vehicle or leptin plasmids into STZ mice to achieve chronic hyperleptinemia (0.2±0.02 and 433±90 ng/ml on days -1 and 19). In contrast to HFD feeding, chronic hyperleptinemia lowered blood glucose levels long term (4.7±0.8 and 11.5±2.4 mM on days 19 and 123). In a new cohort of mice, delivery of plasmid encoding leptin led to chronic hyper-leptinemia (2±0.3 and 131±21 ng/ml on day -1 and 104). We then injected STZ, which increased blood glucose levels in mice with pre-existing hyper-leptinemia comparable to that of controls (19.5±1.0 and 22.4±0.9 mM on day 10 post-STZ) despite maintenance of hyperleptinemia (108±18 ng/ml). HFD can both block and reverse the antidiabetic actions of leptin. Pre-exist-ing chronic hyperleptinemia leads to resistance in the antidiabetic actions of leptin but is insufficient to reverse the antidiabetic actions of leptin in the absence of HFD feeding.Supported By: Canadian Institutes of Health Research

2057‑PImpact of Mineralocorticoid Receptor Blockade on Energy Metabo‑lism and NLRP3‑Inflammasome Activation in Diet‑Induced Obese MiceAKARI ISHIKAWA, TSUTOMU WADA, ERI WATANABE, HAYATE HASEGAWA, YUTO NAKAMURA, HIROSHI TSUNEKI, YOKO ISHII, MASAKIYO SASAHARA, TOSHIYASU SASAOKA, Toyama, Japan

Activation of renin-angiotensin-aldosterone system in obesity is a crucial pathophysiology with insulin resistance. We have previously demonstrated beneficial effects of eplerenone (Ep), a selective mineralocorticoid recep-tor (MR) antagonist, on the obesity-associated glucose intolerance. In this study, we aimed to clarify the underlying mechanism by focusing on energy metabolism and NLRP3-inflammasome activation. C57BL6 mice were fed a regular diet or a 60% high-fat diet (HFD), with or without Ep at 1.67 mg/g. Phenotypes of each mouse were analyzed after 12 weeks of feeding. Treat-ment with Ep significantly prevented from HFD-induced body weight gain and fat accumulation, and ameliorated glucose intolerance and insulin resis-tance, whereas food consumption was not altered. The reduction of body fat was attributed to the enhanced energy metabolism in the mice. Importantly, Ep significantly attenuated accumulations of CD11c+ M1-macrophage (MΦ)

body weight or the fat/lean mass ratio in HFD groups (p>0.05). Grip strength (N) (untrained: 1.54±0.08; END: 1.66±0.11; HIIT: 1.69±0.10) and maximal running capacity (m) (untrained: 196±49; END: 430±51; HIIT: 485±98) were similarly higher in END and HIIT groups compared to untrained HFD (p<0.05). END nor HIIT changed muscle triglyceride in the HFD groups (p>0.05), and only HIIT improved insulin sensitivity (0.65 IU insulin/kg*BW) in HFD mice (p<0.05). In CHOW mice both programs increased muscle collagen VI depo-sition (untrained: 1.0±0.2; END: 1.6±0.4; HIIT: 2.0±0.4; p<0.05), which was seen only after HIIT in HFD animals (untrained: 1.3±0.3; END: 1.2±0.2; HIIT: 1.7±0.2; p<0.05). While CTGF levels were higher after HFD (~2-fold change) and no effect of exercise was seen, HFD promoted a down-regulation of TGF beta (untrained: 0.5±0.1; END: 0.5±0.1; HIIT: 0.9±0.3; p<0.05) and of Deco-rin (untrained: 0.75±0.1; END: 0.71±0.1; HIIT: 1.1±0.1; p<0.05), and only HIIT reversed these changes. Thus END and HIIT promoted similar benefits in muscle function, however increased insulin resistance and changes in the extracellular matrix were reversed only after HIIT. This data suggest that HIIT may be preferred to END as an exercise treatment regimen in estab-lished obesity.

Supported By: Becas Chile; Australian National Health and Medical Research Council

2054‑PImeglimin Protects from Diabetic Cardiomyopathy in the Obese Zucker RatMARIANNE LACHAUX, LIONEL NICOL, MOUAD HAMZAOUI, PASCALE FOU-QUERAY, SÉBASTIEN BOLZE, SOPHIE HALLAKOU-BOZEC, VINCENT RICHARD, PAUL MULDER, Rouen, France, Lyon, France

Background: Imeglimin is a novel glucose lowering agent, which targets mitochondrial bioenergetics, decreases ROS overproduction, delays mPTP opening and prevents cell death during oxidative stress. Whether Imeglimin also exhibits protective effects on diabetic cardiomyopathy, i.e., left ven-tricular (LV) diastolic dysfunction, is unknown.

Methods: Zucker fa/fa rats, a model of metabolic syndrome, were treated for 12 weeks with Imeglimin (150 mg/kg BID PO) to assess effects on LV function and LV hemodynamics (echocardiography, MRI, LV catheterization).

Results: Untreated Zucker rats presented LV diastolic dysfunction (increased LV end-diastolic pressure (LVEDP; mm Hg), LV relaxation constant Tau (ms) and LV end-diastolic pressure volume relation (LVEDPVR; mm Hg/relative volume unit)) associated with reduced cardiac output (CO; ml/min) and LV tissue perfusion (ml/min/g of tissue), but without changes in LV end-systolic pressure volume relation (LVESPVR; mm Hg/relative volume unit). Imeglimin significantly reduced LVEDPVR, improved Tau and increased CO as well as LV tissue perfusion. Moreover, Imeglimin improved glucose toler-ance.

Conclusion: Long-term Imeglimin prevents LV diastolic dysfunction in a rat model of metabolic syndrome, suggesting that Imeglimin may exert protec-tive effects on diabetic cardiomyopathy characterized by a LV diastolic dys-function present in half of type 2 diabetic patients.

Table. Cardiac Function and Hemodynamics.Groups CO LVESP LVESPVR LVEDP Tau LVEDPVR Myocardial

Tissue PerfusionLean 137±4 105±6 21.6±1.7 2.25±0.35 7.19±0.19 0.87±0.17 6.16±0.26Zucker 103±4* 129±5* 24.3±1.6 3.75±0.24* 8.29±0.26* 3.63±0.24* 4.28±0.35*Zucker+Imeglimin 124±5† 120±5 25.4±1.2 3.06±0.34 6.96±0.15† 1.80±0.11† 5.68±0.13†*:p<0.05 vs. lean; †: p<0.05 vs. Zucker.

Supported By: Poxel SA

2055‑PAnagliptin, a DPP‑4 Inhibitor, Attenuates Diet‑Induced Obesity by Modulating Adipose Tissue Angiogenesis in MiceWATANABE ERI, WADA TSUTOMU, ONOGI YASUHIRO, TSUNEKI HIROSHI, SAS-AOKA TOSHIYASU, Toyama, Japan

White adipose tissue expands in obesity depending on angiogenesis. Recently, we found the significant role of PDGF-B on adipose tissue angio-genesis and tissue expansion in obesity. Stromal cell derived factor 1 (SDF1) is another proangiogenic factor functionally correlated with PDGF-B; however, it is still unclear how these two factors cooperatively involves in adipose tissue angiogenesis. Mature vessels in the epididymal white adipose tissue (eWAT) are tightly wrapped with pericytes (PCs). We found that obesity-associated increase of PDGF-B promoted detachment of PCs from nature vessels; thereby vessels were prone to vascular sprouting. To investigate the relationship between PDGF-B and SDF1, we performed

A542


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—ANIMAL

assess the role of estrogen on EPO metabolic response, female mice were ovariectomized (OVX). EPO or estradiol plus HFD treatment in OVX mice decreased body weight gain, and EPO plus estradiol was no more effective than estradiol alone. These data provide an explanation for the apparent sex-linked protective effect of EPO against DIO and suggest that the protec-tive effect of EPO against DIO is only evident in male mice due to lack of the protective estrogen effect against DIO.

2060‑PNatural Brown Adipose Expansion Correlates with Metabolic Res‑olution in Obese MiceCARYN CARSON, SAKURA OYAMA, JESSICA P. WAYHART, HEATHER LAWSON, St. Louis, MO

Obesity is a major public health problem in the U.S. and worldwide due to its growing prevalence and causal relationship with medical complications. We have identified a mouse strain that develops hallmark characteristics of metabolic disease when fed a high-fat diet, but resolves these characteris-tics between 20 and 30 weeks of age. These mice remain obese and develop visibly hypertrophic interscapular adipose tissue depots concurrently with improved glucose tolerance and lower fasting glucose and triglycerides levels. Histological analysis reveals the hypertrophic adipose depot is com-posed of brown adipocytes with small, multilocular lipid droplets and strong UCP-1 expression. Average adipocyte size increases from 400 μm2 at 10 weeks to 700 μm2 at 20 weeks of age, but does not change between 20 and 30 weeks. The mitotic index, as measured by % of cells with positive phosphohistone H3 staining, is highest in 10 week old animals at 11% but decreases to below 1% at 20 and 30 weeks. Brown adipose tissue gene expression was evaluated between high- and low-fat fed mice (42% and 16% calories from fat; n = 8 in each diet) and gene functional classifica-tion analysis (DAVID) revealed enrichment of differentially expressed genes involved in cytokine activity (fold enrichment = 18.81; FDR corrected p-value = 0.001). These results suggest that non-thermogenic brown adipose tissue activity may underlie the metabolic resolution in these obese mice. Inves-tigation of the genetic and epigenetic mechanisms underlying this phenom-enon in mice may lead to novel brown-adipose mediated therapeutic targets for metabolic dysfunction in obese people.

Supported By: Washington University School of Medicine Nutrition Obesity Research Center (P30DK056341); National Institutes of Health (K01DK095003)

2061‑PIdentification of Soluble EGFR as a Serum Biomarker of Insulin Resistance by a Quantitative Proteomic Analysis Using Mice with DiabetesMAYU KYOHARA, JUN SHIRAKAWA, AYUKO KIMURA, HISASHI HIRANO, YASUO TERAUCHI, Yokohama, Japan

The db/db mice exhibit morbid obesity, hyperglycemia and insulin resis-tance gradually with age and ultimately to develop diabetic complications. To identify circulating factors as candidates involved in the development of diabetes, we conducted 2 different quantitative proteomic analyses: 1) db/db mouse sera were compared with db/+ mouse sera obtained at 4, 8, 12 and 24 weeks of age (n = 4-6), and 2) db/db mouse sera from animals treated with liraglutide were compared with sera from animals without liraglutide treatment (n = 5). In the first experiment, 6 proteins were differentially expressed in db/db mouse sera across all ages: epidermal growth factor receptor, fetuin-B, MCG15829, isoform CRA_a, properdin, oxidation resis-tance protein 1, and vascular cell adhesion protein 1 (ANOVA, P value <0.05). In the second experiment, 22 and 11 proteins were significantly increased (e.g., haptoglobin, serine protease inhibitor A3K) and decreased (e.g., fibrino-gen α-chain, CD5 antigen-like) in db/db mouse sera treated with liraglutide (ANOVA, P value <0.05). Among them, soluble epidermal growth factor receptor (sEGFR) was identified as a common factor, and its protein level was significantly affected in both experiments. An ELISA assay confirmed that the significantly low serum sEGFR levels in db/db mice were restored by liraglutide treatment. The serum sEGFR levels were decreased in high-fat diet-fed mice. In human subjects with type 2 diabetes (n = 27) or normal glucose tolerance (n = 15), the serum sEGFR levels were positively correlated with the fasting blood glucose levels (r=0.49, p<0.01), HbA1c (r=0.39, p=0.01) and HOMA-R (r=0.37, p=0.03). Taken together, these findings suggest that sEGFR might be a biomarker for evaluating insulin resistance or a therapeutic target of liraglutide.

and reduction of CD206+ M2-MΦ in the epididymal white adipose tissue (eWAT) of HFD-fed mice. Consistently, increased mRNA expressions of Il1b, Il6 and Tnfa were attenuated in the eWAT and liver. Since Ep effectively attenuated aldosterone- or LPS-induced ROS production as a typical danger signal in bone marrow-derived MΦ (BMDM), we next examined the effects on NLRP3-inflammasome activation. Ep effectively suppressed expressions of NLRP3 and Caspase1 in the eWAT and liver of HFD mice. The secretion of IL-1β from eWAT was also decreased. Moreover, Ep effectively suppressed enhanced IL-1β secretion by LPS with ATP or nigericin in BMDM.

In conclusion, MR blockade improved glucose intolerance with obesity in mice. Ep appears to enhance energy metabolism and inhibit NLRP3-inflam-masome activation, resulting in the attenuation of chronic inflammations in the adipose tissue and liver.

2058‑PErythropoietin Regulates Metabolic Response in Mice via Its Receptor Expression in White Adipose TissueCONSTANCE T. NOGUCHI, HEATHER M. ROGERS, Bethesda, MD

Erythropoietin (EPO) is required for red blood cell production. The increase in hematocrit with EPO treatment in adult (8 months) wild type (WT) male mice (C57Bl/6) has been associated with a 14% decrease in body weight, suggesting a metabolic burden associated with increased erythropoiesis. However, mice that lack EPO receptor (EpoR) in non-hematopoietic tissue treated with EPO exhibit increased hematocrit without change in body weight, suggesting that change in body weight with EPO treatment may not be related to increased erythropoiesis. Among non-hematopoietic tissues, EpoR expression is relatively high in white adipose tissue (WAT). We gener-ated mice with EpoR deletion in fat tissue (TgEpoR). At 12 weeks, WT and TgEpoR male mice on high fat diet (HFD) for 3 weeks showed little differ-ence in body weight or body composition. EPO treatment (3000U/kg 3X per week) plus HFD for 3 weeks resulted in increased hematocrit (60 to 65%) and improved glucose tolerance in both WT and TgEpoR male mice. In older mice (6 months) with greater % fat mass, EPO treatment plus HFD for 3 weeks in WT male mice showed increased hematocrit and improved glucose toler-ance, and EPO protection against diet-induced obesity (DIO) with decreased % fat mass, and decreased body weight. In contrast, TgEpoR male mice similarly treated showed increased hematocrit with only minimal change in glucose tolerance and without protection against DIO with no change in fat mass or body weight. These data suggest that the metabolic burden of EPO stimulated erythropoiesis is associated with decreased blood glucose and improved glucose tolerance observed in young WT and TgEpoR mice. How-ever, as mice age and fat mass increases, with EPO treatment, the improve-ment in glucose tolerance due to EPO stimulated erythropoiesis decreases and EPO protection against DIO becomes evident, mediated by non-hemato-poietic tissue response, particularly EpoR expression in fat tissue.Supported By: National Institute of Diabetes and Digestive and Kidney Diseases; National Institutes of Health

2059‑PGender Specific Metabolic Response to Erythropoietin In MiceHEATHER M. ROGERS, YUANYUAN ZHANG, CONSTANCE T. NOGUCHI, Bethesda, MD

Erythropoietin (EPO) is the cytokine required for erythrocyte production. However, EPO receptor (EpoR) expression is not restricted to erythroid tissue and non-hematopoietic EPO action has been associated with the regulation of glucose homeostasis and fat mass accumulation in animal models. Wild type (WT) male mice (C57BL/6) at 6 months fed a high-fat diet (HFD, 60% kCal fat) and treated with Epo (3000U/kg 3X per week) for 3 weeks show the concomitant increase in hematocrit, improvement in glucose tolerance, and decrease in both weight and fat mass compared to HFD/saline treat-ment. Male mice with targeted deletion of EpoR in fat tissue (DEpoRWAT) at 6 months fed a HFD and treated with Epo for 3 weeks show the increase in hematocrit, but minimal change in glucose tolerance and no change in fat mass/body weight compared to HFD/saline treatment. These data sug-gest a protective effect of EPO against diet-induced obesity (DIO) mediated via EPO response in EpoR expressing fat tissue. In contrast, WT female mice at 6 months fed a HFD and treated with Epo for 3 weeks show the concomitant increase in hematocrit and improvement in glucose tolerance with no change in weight or fat mass when compared to HFD/saline treat-ment, despite EpoR expression in fat tissue, indicating that the protective effect of EPO against DIO is only evident in male mice. Similarly, DEpoRWAT female mice at 6 months fed a HFD and treated with Epo for 3 weeks show the increase in hematocrit and improvement in glucose tolerance with no change in weight or fat mass when compared to HFD/saline treatment. To

A543


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—ANIMAL

2064‑PLinagliptin Reduces the Pro‑fibrotic LARP6 Expression in Hearts of Female Mice Fed a Western DietANNAYYA R. AROOR, KANDIKATTU HEMANTH KUMAR, JAVAD HABIBI, MEGAN S. JOHNSON, THOMAS KLEIN, JAMES R. SOWERS, BYSANI CHANDRASEKAR, VINCENT G. DEMARCO, Columbia, MO, Biberach, Germany

There is no treatment for cardiac fibrosis, a major contributing factor for diastolic dysfunction and heart failure development, especially in women. Previously we reported that feeding mice a Western Diet (WD) high in fat and simple sugars induces excess deposition of type 1 collagen (Col1), the major extracellular matrix protein largely responsible for interstitial fibrosis and impaired cardiac diastolic relaxation. We also reported that the DPP-4 inhibitor, linagliptin, prevents myocardial fibrosis and diastolic dysfunction in these mice. However, the mechanisms responsible for these functional improvements have yet to be determined. Recent reports indicate that the novel RNA binding protein, LARP6 (La Ribonucleoprotein domain family, member 6) post-transcriptionally regulates the expression of Col1α1. It is however not known whether WD induces LARP6 expression, whether LARP6 expression correlates with interstitial fibrosis in the heart, and whether lina-gliptin inhibits its induction. Female 4 week-old mice were fed a WD with or without linagliptin (83mg·kg-1diet) for 16 weeks. The results show that the WD-induced interstitial fibrosis was associated with a 2.5-fold induction in LARP6 expression in the heart. Importantly, linagliptin inhibited its induction and that of several other profibrotic genes, including Col1α1, Col3α1, lysyl oxidase and CTGF. These results demonstrate for the first time the induction of LARP6 in the heart of a translationally relevant model of diet-induced obesity. Therapeutic targeting of DPP-4 with linagliptin or pharmacological inhibition of LARP6 may be a promising strategy for prevention of cardiac fibrosis and diastolic dysfunction in obese and/or diabetic females.

Supported By: Boehringer Ingelheim; National Institutes of Health; U.S. Depart-ment of Veterans Affairs

2065‑PZinc Alpha2 Glycoprotein Protects against Hepatis Steatosis and Inflammation in Obese MiceYADI WANG, XINHUA XIAO, XIAOYAN QI, HAN LI, GEXIN LIU, GEBO WEN, JIAN-GHUA LIU, Hengyang, China

Zinc alpha2 glycoprotein (ZAG) has recently been characterized as a lipid-mobilizing factor in combating adiposity. However, the molecular mecha-nisms of ZAG against obesity and comorbidities remain largely unexplored. This study investigates a deeper insight of ZAG in controlling the progression of obesity-associated hepatosteatosis, inflammation and insulin resistance. First, we found ZAG expression was significantly decreased in the livers of nonalcoholic fatty liver disease (NAFLD) patients and of obese mice as well as in cultured hepatocytes stimulated with palmitate. Further investigation indicated that specific overexpression of ZAG in hepatocytes enhanced insulin sensitivity and glucose tolerance via activation of insulin receptor substrates/phosphatidylinositol-3-kinase/Akt (IRS/PI3K/Akt) signaling path-way in obese mice. Simultaneously, ZAG could ameliorate hepatic lipid accu-mulation via upregulating adiponectin and lipolytic genes (FXR, PPARα, etc) while downregulating lipogenic genes (LXR, SREBP-1c, etc) in obese mice as well as in cultured hepatocytes stimulated with palmitate. Moreover, overexpression of ZAG can significantly inhibite nuclear factor kappaB (NF-κB) and c-Jun-N-terminal kinase (JNK) signaling pathway and thus result in suppression of obesity-associated inflammatory response in hepatocytes. Collectively, these data suggest that ZAG could have a potential ability to alleviate NAFLD/NASH and serve as insulin sensitizer.

Supported By: National Natural Science Foundation of China (81270925)

2066‑PIntermedin Inhibited Adipose Tissue Inflammation in High‑Fat Diet‑Induced Obese MiceHENG ZHANG, XIAN WANG, GUANG WANG, Beijing, China

Objective: Chronic inflammation in adipose tissue is one of the main pathogenesis of insulin resistance and type 2 diabetes. Intermedin (IMD) is a novel member of the CGRP family. The aim of this study is to determine whether IMD could improve chronic inflammation in adipose tissue in high fat diet (HFD)-induced obese mice.

Material and Methods: C57 mice were fed with chow or high fat diet for 8 weeks. From the fifth week, osmotic pumps filled with IMD (300ng/kg/hour) or saline were planted subcutaneously. For in vitro study, primary rat adipocytes and fully differentiated 3T3-L1 adipocytes were used.

Results: HFD significantly impaired insulin sensitivity in C57 mice assessed by Glucose tolerance test and insulin tolerance test. When the

2062‑PAngiotensin‑(1‑7) Attenuates Weight Gain and Adipose Tissue Inflamma tion during High‑Fat Feeding in MiceTRACI A. CZYZYK, TIMOTHY K. COOPER, SARAH BINGAMAN, AMY C. ARNOLD, Hershey, PA

Over activation of the renin-angiotensin system, and in particular angio-tensin (Ang) II, contributes to obesity-induced insulin resistance via mul-tiple mechanisms. Obesity is also associated with deficiency of Ang-(1-7), a vasodilatory peptide that opposes Ang II actions. Our recent study showed that chronic Ang-(1-7) treatment reduces adiposity and reverses whole-body insulin resistance in obese mice independent of effects on blood pressure. In this study, we tested the hypothesis that Ang-(1-7) could prevent high fat diet-induced weight gain and insulin resistance, and identified potential mechanisms involved in this effect. Adult male C57BL/6J mice received a 12-week infusion of Ang-(1-7) (400 ng/kg/min; n=7) or saline (n=6) via subcu-taneous osmotic mini-pumps. Mice were placed on a 60% high fat diet (HFD) immediately following mini-pump implantation. Body composition, energy balance, and insulin sensitivity were measured during the last week of treat-ment. Ang-(1-7) attenuated HFD-induced weight gain (39.7±1.3 vs. 43.9±0.7 g saline; p=0.023) and adiposity (32±1 vs. 29±1% saline; p=0.050). The weight-reducing effect was due to enhanced energy expenditure, without signifi-cant changes in locomotor activity or food intake. Ang-(1-7) improved the ability of intraperitoneal insulin to decrease blood glucose levels in obese mice (20% reduction in area under the curve vs. saline; p=0.015), consis-tent with its known insulin-sensitizing effects. To evaluate the effect on adiposity, we performed blinded histological analysis of epididymal white adipose tissue. Ang-(1-7) reduced discrete foci of adipose inflammation as measured by the mean number of crown-like structures (3±1 vs. 8±2 saline; p=0.046), with no effect on adipocyte size. These findings suggest that tar-geting Ang-(1-7) may represent a novel strategy to attenuate development of obesity-induced insulin resistance, perhaps by improving adipose tissue inflammation.


2063‑PMetformin Treatment Enhances Endothelial Nitric Oxide Bioavail‑ability in Obese Zucker Rats in a Manner Not Predicted by Glucose ControlTAKEHIKO SAMBE, R.P. MASON, TADEUSZ MALINSKI, DEEPAK L. BHATT, Boston, MA, Beverly, MA, Athens, OH

Endothelial cell (EC) dysfunction is related to atherosclerosis and is asso-ciated with cardiovascular risk factors such as diabetes. Loss of nitric oxide (NO) is evidence of EC dysfunction. We tested the vascular effects of metfor-min in an animal model of obesity and insulin resistance. Beyond its effects on glucose control, metformin may have direct EC benefits through modula-tion of NO synthase (NOS) activity. Obese Zucker rats were maintained on a high-fat diet and administered vehicle or 300 mg/kg/day metformin for 4 weeks. NO and peroxynitrite (ONOO−) release from aortic and glomerular EC was measured ex vivo using amperometric approaches and correlated with fasting glucose levels. Rats showed evidence of pronounced endothelial dysfunction and loss of NO bioavailability with the high-fat diet; compared with baseline, aortic and glomerular endothelial NO release was reduced by 32% (p<0.001) and 41% (p<0.001), respectively, while ONOO− release was increased by 79% (p<0.001) and 69% (p<0.001). Metformin largely reversed the progression of endothelial dysfunction due to the high-fat diet in these animals. Metformin increased aortic and glomerular endothelial NO release by 37% (299 ± 57 nM to 411 ± 51 nM, p<0.01) and 57% (110 ± 14 nM to 173 ± 21 nM, p<0.001) while decreasing ONOO− release by 32% (p<0.001) and 34% (p<0.001), respectively, compared with vehicle-treated controls. The NO/ONOO− release ratio, an indication of eNOS coupling efficiency, increased with metformin treatment by 101% (0.97 ± 0.23 nM to 1.95 ± 0.40 nM, p<0.0001) and 138% (0.66 ± 0.11 nM to 1.57 ± 0.28 nM, p<0.0001) in aortic and glomerular ECs, respectively. By contrast, fasting glucose levels were not significantly changed by metformin. These findings indicate that metformin therapy has direct effects on arterial and renal EC function in obese rats, including enhanced NO release and reduced nitroxidative stress, beyond any effects on fasting glucose levels.

A544


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—ANIMAL

and leptin resistance. We measured ATP concentrations in the hypothala-mus of high fat diet-induced obese (DIO) mice with celastrol or withaferin A treatment. We found that hypothalamic ATP concentrations in DIO mice were significantly decreased when compared with lean control mice but were increased by celastrol or withaferin A treatment for 3 days. At this time, expressions of ER stress markers including phosphorylated PERK were decreased and leptin sensitivity were improved. These results indicate that the ATP deficiency plays an important role in the development of ER stress and leptin resistance in the hypothalamus and that celastrol and withaferin A alleviate ER stress and restore leptin sensitivity through up-regulating ATP concentrations in the hypothalamus.

2069‑POkra Polysaccharide Ameliorating Glucose Metabolism and Acti‑vating AMPK in Insulin‑Resistant MiceLIN CHEN, CUIPING ZHANG, MING LU, YULI CAO, TAO LEI, BILIN XU, Shanghai, China

Objectives: To observe the effect of okra polysaccharide (OP) on glucose metabolism in insulin resistant mice induced by high fat diet and to discuss the possible mechanisms.

Methods: Forty male CD47/BL mice were divided into 4 groups (the OPL, OPH, S, and H groups) and fed with high fat diet. After 8 weeks, OPL, OPH, and S groups were given low dose OP (150mg/·kg-1·d-1), high dose OP (300mg/·kg-1·d-1), and sitagliptin (10mg/·kg-1·d-1) by daily gavage respectively. And H group was simultaneously perfused with the same volume of saline. After 10 weeks, glucose tolerance test (OGTT), pyruvic acid tolerance test (PTT), and insulin tolerance test (ITT) were undertaken and the levels of some key enzymes involved in gluconeogenesis in liver were detected. Hepatic glycogen deposition was observed using periodic acid schiff (PAS) staining.

Results: OGTT showed that OPL group had lower glucose levels at 60 minutes than H group, and the glucose levels at 30 and 60 minutes in OPH group were significantly lower than those of H group. During PTT, compared with H group, OPL group had decreased glucose levels at 15 and 30 minutes and the glucose levels in OPH group also went down at 15, 30, and 60 min-utes. ITT showed that OPH group had better insulin sensitivity than H group. Compared with H group, expressions of PEPCK, PGC-1α, and KLF15 mRNA and the protein levels all decreased in OPH and OPL groups. Meanwhile, increased expression of AMPK mRNA and its phosphorylation were found in OPH group. PAS staining showed that OPH group had more hepatic gly-cogen deposition than H group. All differences had statistical significance. However, there is little statistical difference in gluconeogenesis between S and H groups although S group had significantly decreased glucose levels during OGTT and ITT.

Conclusions: Our study suggests that okra polysaccharide ameliorates glucose metabolism in insulin resistant mice, which probably relates to increased levels of AMPK and its phosphorylation.

2070‑Pd‑δ‑Tocotrienol Inhibits High‑Fat Diet‑Induced Hepatic Inflamma‑tion by Downregulating STAT3 SignalingSHALIGRAM SHARMA, HUANBIAO MO, CHWAN LI SHEN, DESIREE WANDERS, Atlanta, GA, Lubbock, TX

Tocotrienols are members of the vitamin E family whose anti-inflamma-tory effects have been widely reported in cancer cell models. However less is known about their anti-inflammatory properties in rodent models of obesity. Accompanying obesity is a chronic, low-grade inflammation that links obesity to metabolic disorders, including insulin resistance and type 2 diabetes. d-δ-Tocotrienol has been shown to reduce high-fat diet (HFD)-induced inflammatory gene expression in adipose tissue and improve plasma glucose levels in rodents. Little is known about the mechanism by which d-δ-tocotrienol decreases inflammation. The objectives of the current study were to 1) determine whether d-δ-tocotrienol inhibits HFD-induced hepatic inflammation, and 2) identify the mechanism by which d-δ-tocotrienol decreases HFD-induced inflammation in vivo. Male C57BL/6 mice aged 5-6 weeks were fed a low-fat control diet (n=9), a high-fat control diet (n=12), or a high-fat diet supplemented with d-δ-tocotrienol (400 mg/kg diet; n=9) for 14 weeks. mRNA expression of inflammatory and anti-inflammatory mark-ers (Ccl2, Emr1, Itgax, Il6, Tnf, Ifng, Il23, Socs3, Il2, Il10,) was measured in liver. Western blot analysis was conducted to measure phosphorylation of the generally pro-inflammatory transcription factor, STAT3. HFD increased hepatic inflammation, and STAT3 phosphorylation (activation) compared to low-fat diet-fed mice. d-δ-Tocotrienol decreased inflammatory gene expres-sion in liver, with a concomitant reduction in STAT3 phosphorylation to levels seen in the low-fat diet-fed mice. d-δ-Tocotrienol suppressed hepatic inflam-

mice were administered with IMD for 4 weeks, they showed lower fasting blood glucose and insulin levels. IMD improved HFD-induced insulin resis-tance confirmed by Glucose tolerance test and insulin tolerance test without alterating mouse food intake. HFD mice showed increased levels of plasma inflammatory cytokines (TNFα, IL-6, MCP-1) than chow diet fed mice, while IMD treatment significantly lowered these increases. In addition, histologi-cal analysis of H&E- and immuno-stain showed much smaller lipid droplet, less crown like structures, and much less inflammatory cell infiltration in adi-pose tissue from IMD group. And IMD treatment also significantly decreased HFD-enhanced inflammatory cytokine levels in adipose tissue assessed by immuno-stain and real-time PCR. Pretreating primary rat adipocytes and 3T3-L1 with IMD attenuated TNFα-induced inflammatory cytokines’ mRNA expression and secretion. And TNFα induced, IκBα degradation, p65 nuclear-translocation and NF-κB activity were all reduced by IMD.

Conclusions: These results indicate that IMD treatment improves insulin resistance in HFD mice, and the underlying mechanisms may involve sup-pressing chronic inflammation in adipose tissue.

2067‑PThe Relation between Epigenome Changes of KLF14 Region and Chronic Inflammation in Obese MiceCHIHIRO IWAYA, YUKA KIMURA, YOSUKE IKEDA, HIDETOSHI KITAJIMA, KEN YAMAMOTO, HIROKI SHIBATA, YASUTAKA MAEDA, NORIYUKI SONODA, YOSHI-HIRO OGAWA, TOYOSHI INOGUCHI, Fukuoka, Japan, Oxford, United Kingdom, Kurume, Japan

It has been well known that DNA methylation is functionally relevant modification of the genome, which does not involve a change in the nucleo-tide sequence and allows dynamic changes of biological phenomena by con-trolling gene expression. Previously, we identified reproducibility and organ specificity of methylation change on db/db mouse KLF14 promoter region (0.25kb upstream) that were consistent with the significant change in human population samples. Such methylation changes were significantly correlated with weights and blood glucose levels. Although it had been reported that KLF14 gene appears to be a master regulator of gene expression in adipose tissue and associate with T2D in large GWAS study, the detailed mechanism underlying the link between KLF14 and T2D is poorly understood. To extend our knowledge on the mechanisms, we performed bisulfite sequencing on the high-fat diet mouse KLF14 promoter region (0.25kb upstream). C57BL/6J mice were fed a high-fat diet (HFD: 60% kcal by fat) or a normal diet (NFD: 11% kcal by fat). Mice were dissected at the age of 9 weeks, which they were fed HFD or NFD for 4 weeks, and various organ specimens were prepared. Then, we carried out the bisulfite sequencing on the region corresponding to that of human KLF14. We found that DNA methylation levels of these sites were increased with weights in the particular organ including spleen, adipose tissue, and blood. In addition, these changes were also significantly associated with inflammatory factors including serum levels of TNFα and IL12. Taken together, our results suggested that change of methylation levels of KLF14 promoter region correlated with weights is physiologically impor-tant because this change was conserved between human and mouse. Con-sidering the organ specificity and correlation with inflammatory changes, it is possible that KLF14 is related to immunity on adipose tissue.


2068‑PCelastrol and Withaferin A Restore the Sensitivity of the Hypothala‑mus to Leptin through Upregulating ATP ConcentrationCHIHIRO EBIHARA, KEN EBIHARA, MASAYO ISODA, AKIKO MURAKAMI, DAISUKE YAMAMURO, MANAMBU TAKAHASHI, SYUICHI NAGASHIMA, SHUN ISHIBASHI, Tochigi, Japan, Shimotsuke, Japan

Leptin is an adipocyte-derived hormone involved in the regulation of food intake and energy expenditure. Obese subjects generally have hyperlepti-nemia and leptin resistance. Although the precise mechanism underlying leptin resistance is still unclear, it has been reported that endoplasmic reticulum (ER) stress in the hypothalamus plays a key role. Recently, two natural compounds, celastrol and withaferin A, has been identified as leptin sensitizers (Cell 161: 999, 2015, Nat Med 22: 1023, 2016). Both of them alle-viate hypothalamic ER stress and restore the sensitivity of the hypothala-mus to leptin. However, the molecular mechanism by which celastrol and withaferin A alleviate ER stress and restore leptin sensitivity remains com-pletely unknown. Under ER stress, the accumulation of misfolded proteins facilitates the unfolded protein response (UPR) which requires appreciable amounts of ATP. Indeed, ATP-deficient cells are vulnerable to ER stress and treatment of ATP protects cells against ER stress. For these reasons, we investigated the role of ATP in the development of hypothalamic ER stress

A545


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—ANIMAL

2073‑P

2074‑PAdipose‑Derived VEGF‑A Stimulates Lipolysis through Activation of Sympathetic Nervous SystemYUESHUI ZHAO, XUE GU, KAI SUN, Houston, TX

Obesity is a major risk factor for many epidemic diseases, including type 2 diabetes and cardiovascular disease (CVD). During obesity develop-ment, vascularization of adipose tissue cannot catch up with the pace of rapid expansion of fat mass and local hypoxia thus develops. This process may further lead to fibrosis, inflammation and insulin resistance. Impor-tantly, we recently found that a key angiogenetic factor VEGF-A dramati-cally improves the vascularization in the obese adipose tissue, which hence protects transgenic mice not only against high-fat diet (HFD)-induced obesity but also insulin resistance. However, the precise mechanisms underlining these metabolic phenotypes need to be further investigated. In the cur-rent study, by using a doxycycline (Dox) inducible adipose tissue specific VEGF-A overexpression mouse model, we found that local overexpression of VEGF-A stimulates lipolysis in adipose tissue by upregulating hormone sensitive lipase (HSL) expression and enhancing HSL phosphorylation levels in adipocytes. As the result, the VEGF-A transgenic mice exhibited smaller adipocytes and reduced total fat mass shortly after VEGF-A induction. Intriguingly, the local norepinephrine (NE) levels in adipose tissue were dra-matically increased in the transgenic mice. Immunofluorescent staining (IF) with anti-tyrosine hydroxylase (TH) antibody further showed higher neuron density innervated in the adipose tissue of the transgenic mice. Moreover, the enhanced lipolytic effects were significantly abolished upon treatment with β3-adrenoceptor antagonist SR59230A. These observations clearly suggest that the sympathetic tone activated by VEGF-A plays a key role in adipose tissue lipolysis, which ultimately lead to enhanced energy expen-diture. Results from our investigation provide a greater understanding of the molecular mechanisms by which VEGF-A brings out metabolic benefits.

Supported By: University of Texas Health Science Center at Houston (UL1TR000371)

mation, despite having no effect on body weight, suggesting direct anti-inflammatory effects of d-δ-tocotrienol independent of body weight loss. These findings indicate that d-δ-Tocotrienol mitigates HFD-induced hepatic inflammation by downregulating STAT3 signaling and has potential in the prevention and/or therapy of metabolic disorders.

Supported By: American River Nutrition, Inc.

2071‑PLC3 Blockade Improves Metabolic Profiles in Mice Fed a High‑Fat DietMANNA LI, MING QIAN, JIAN XU, Oklahoma City, OK

Emerging studies link proteostasis to the pathogenesis of obesity and insu-lin resistance. However, the underlying mechanism is not fully elucidated. This study determined the role of an autophagic protein LC3 in a mouse model of obesity induced by a high-fat diet (HFD). Wild type (WT, C57BL/6J, male, 8-10-week-old, n=15/group) mice developed obesity and insulin resis-tance on a HFD (TestDiet 60% energy from fat for up to 3 months); in con-trast, gender- and age-matched mice lacking the LC3b gene (Lc3b-KO, n=15/group) presented with lower body weight gain and less epididymal white adipose tissue (eWAT) mass, and improved intraperitoneal glucose toler-ance test, although with no significant difference in food and water intake. Adipokine array revealed that serum levels of leptin and insulin, but not the metabolically favorable hormone FGF-21, were higher in WT than Lc3b-KO mice fed a HFD; however, levels of endothelial FGF-21 in eWAT were lower in WT than Lc3b-KO mice, determined by immunohistochemistry of FGF-21 and endothelial markers (CD31 and lectin). Mimicking the impacts of HFD on eWAT, palmitate (100 μM, 16 h) reduced FGF-21 expression in HUVEC that was co-cultured with 3T3-L1 adipocytes, but not in LC3b-siRNA-treated HUVEC. Mechanistically, palmitate enhanced LC3b-mediated autophago-some formation in HUVEC that lowered FGF-21 production thereby blunt-ing FGF-21-mediated signaling in co-cultured 3T3-L1 adipocytes. Indeed, in Lc3b-KO, not WT, mice fed a HFD, the FGF-21 (co)receptors (FGFR1c/ β-Klotho) and “surrogates” (UCP1/GLUT1) in eWAT adipocytes remained intact or became upregulated. Concomitant with UCP1 induction, part of eWAT had an appearance of beige-cell-like deposits and fewer expanded adipocytes, typical of browning.

In summary, LC3 mediated high-fat diet-induced obesity and insulin resis-tance in mice, which was associated, at least in part, with HFD-enhanced endothelial FGF-21 loss in adipose tissue. Therapeutic LC3 blockade may be a new approach to treat obesity and insulin resistance in patients.

Supported By: American Diabetes Association (1-12-JF-58 to J.X.); National Institutes of Health

2072‑POverexpression of Hexose‑6‑Phosphate Dehydrogenase in Adipose Tissue Causes Local Adiposity and Insulin Resistance in MiceYANJUN LIU, XIWEN LIU, CARL SIMS, ADAKU UME, KABIRULLAH LUTFY, THEODORE C. FRIEDMAN, Los Angeles, CA

Obesity dramatically increases the risk of developing insulin resistance and type 2 diabetes (T2DM) and is often associated with dysregulation of glucocorticoid metabolism. The prereceptor activation of glucocorticoid production in adipose tissue is controlled by 11β-hydroxysteroid dehydro-genase type 1 (11β-HSD1) coupled with hexose-6-phosphate dehydrogenase (H6PDH). Transgenic mice overexpressing aP2/H6PDH exhibit high intraadi-pose glucocorticoid production and develop intolerance to glucose and insu-lin with elevated abdominal fat mass and dyslipidemia. Here we report novel adverse effects of H6PDH overexpression on adipose lipogenesis and insulin sensitivity in aP2/H6PDH mice. Mice overexpressing aP2/H6PDH exhibited fat accumulation and elevated lipid synthase acetyl-CoA carboxylase (ACC) and ATP-citrate lyase (ACL) expression, but lower adiponectin and browning marker gene CD137 and TBX1 mRNA levels in adipose tissue than wild type (WT) mice. Furthermore, aP2/H6PDH mice had high adipogenic transcrip-tor C/EBPα and PPARγ mRNA levels, but low pThr308 Akt in adipose tissue than WT mice. Additionally, the D-glucose uptake was reduced along with suppression of GLUT4 and insulin signaling in adipose tissue of aP2/H6PDH mice. These data indicate that increased H6PDH expression may contribute to local adipose adiposity and insulin resistance through activation of 11β-HSD1 driven glucocorticoid production.


WITHDRAWN

A546


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—ANIMAL

2077‑PIncreased Inflammatory Intestinal Macrophage Subpopulations after High‑Fat DietTHERESA ROHM, SHEFAA AL ASFOOR, ANGELA J.T. BOSCH, CLAUDIA CAVELTI-WEDER, Basel, Switzerland

Background: Besides the well-established role of chronic inflammation, studies have shown a link between the gastrointestinal (GI) tract and meta-bolic disease, such as altered microbiota, increased inflammatory cytokines in the gut wall and translocation of bacteria and endotoxin. However, a direct mechanism linking GI alterations and metabolic disease remains elusive.

Research Design and Method: Intestinal macrophages (iMacs) were iso-lated from the colon of male colonized or germ-free (GF) C57BL/6 mice fed either a high fat diet (HFD: 60 kcal % fat) or control diet for up to 3 months and characterized by flow cytometry as monocyte derived (CCR2+; “inflam-matory” P1-P2, intermediate P3) and resident subpopulations (CCR2-; anti-inflammatory P4-P5).

Results: After one week, HFD-fed mice showed a 1.5 fold (± 0.7) and 9.1 fold (± 3.9) increase in the inflammatory P1- and P2-iMac subpopulations, respec-tively, when compared to chow-fed controls, which was mirrored by absolute numbers. Followed over 2 weeks, 1 and 3 months, these inflammatory iMacs were constantly increased (i.e., 3 months: P1 1.3 fold ± 0.1, P2 5.7 fold ± 2.9). Interestingly, mice that did not gain weight under HFD lacked this inflammatory iMacs shift. As GF-mice are typically protected from weight gain, we assessed their iMacs profile to substantiate the link to weight gain. Upon chow diet, GF-mice had a similar iMacs distribution as colonized mice, albeit at lower abso-lute numbers. With HFD, however, no increase in P1 and P2 was observed.

Conclusion: We found that HFD intake induces a microbiota-dependent shift towards inflammatory iMacs. We propose that increased inflammatory iMacs potentially trigger low-grade inflammation and are a prerequisite for weight gain in metabolic disease.

Supported By: Swiss National Science Foundation; University of Basel

2078‑PEffects of Acetyl‑L‑Carnitine on Substrate Switching in High‑Fat Diet‑Induced ObesityJUNG HEE HONG, YOU BIN LEE, JUNG HEE LEE, MOON KYU LEE, Seoul, Republic of Korea

Accumulation of triglyceride in skeletal muscle is associated with insulin resistance in obesity. Recently, it has been suggested that acetyl-l-carnitine (ALC) improves insulin sensitivity by lowering triglyceride accumulation in non-adipose tissues via activation of skeletal muscle AMP-activated protein kinase (AMPK). Carnitine acetyltransferase (CrAT) is a mitochondrial matrix enzyme that catalyzes the interaction of acetyl-CoA and acetylcarnitine. Emerging evidence suggests that this enzyme functions as a positive regula-tor of total body glucose tolerance and activity of pyruvate dehydrogenase (PDH) in muscle, a mitochondrial enzyme complex that promotes glucose oxidation and inhibited by acetyl-CoA. We examined whether chronic ALC supplementation prevents high-fat diet-induced muscular lipid accumulation via activation of AMPK. In addition, we tested whether ALC supplementa-tion was able to improve insulin sensitivity in mice fed with high-fat diet (HFD). Supplementation of ALC (10g/kg body weight) for 8 weeks on male C57BL/6J mice significantly reduced body weight (-15.02% HFD+ALC vs. HFD, P<0.05). Proton magnetic resonance spectroscopy (1H-MRS) revealed 4.7-fold lower lipid contents in skeletal muscle in 10 g ALC-supplemented group compared with HFD group (P<0.05). ALC improved whole body glucose tolerance (~20% lower area under the curve (AUC) of glucose concentration in ALC supplemented groups vs. controls, P<0.05). These effects were medi-ated by muscular AMPK activation and improvement of muscular insulin sen-sitivity. These results suggest that ALC may prevent HFD-induced muscular lipid accumulation and improve the whole body glucose tolerance.

2079‑P

2075‑PUse of the EndoBarrier in a Canine ModelREBECCA L. PASZKIEWICZ, MIGUEL BURCH, ISAAC ASARE BEDIAKO, HAS-MIK MKRTCHYAN, STELLA P. KIM, MARILYN ADER, RICHARD N. BERGMAN, Los Angeles, CA, West Hollywood, CA

For decades the scientific community has known about the effects of bar-iatric surgery on not only weight loss but, more remarkably, on the remission of type 2 diabetes (T2D). Yet, the mechanism for how this remission occurs has yet to be elucidated. The ultimate goal of this current study is 1) to estab-lish a large animal model of bariatric surgery to compare the changes in glucose homeostasis before and after the implantation of the EndoBarrier and 2) to elucidate the mechanism responsible for remission of T2D. We have successfully placed the EndoBarrier in 7 lean male, mongrel hounds (>1 year old) with normal glucose homeostasis. To implant the device, access to the stomach and small intestine was done through a standard endoscope under general anesthesia. The EndoBarrier was placed in the proximal duo-denum using fluoroscopy and the anchor of the device was deployed after full extension of the 60 cm sleeve. Dogs were treated with a proton pump inhibitor throughout the duration of EndoBarrier implantation and were given anti-emetics and analgesics for the first few days following the procedure. Six of 7 dogs returned to a normal chow diet after 3 days of liquid to semi-liquid diet. Fasting blood samples, weight, and food intake were measured weekly. Intravenous glucose tolerance tests (IVGTTs) and oral mixed-meal tolerance tests (MMTTs) were performed prior to implantation of the Endo-Barrier (Baseline) and at one-week post-insertion (week 1). In all animals, some weight loss (-8%, n=7) and decrease in food intake (-22%, n=7) was seen during the week following implantation with a general recovery in both weight (-3% from Baseline to week 5, n=2) and food intake (+33% at week 3, n=3) seen in the following weeks. Fasting glucose remained steady from Baseline to week 1 (-2%, n=7).


2076‑PDifferences in Gut Microbiota and Brown Adipose Tissue Thermo‑genesis Determine the Sensitivity or Resistance to High‑Fat Diet‑Induced ObesityXIAOQIU XIAO, LINGLI LIU, YANBIAO AI, YI HOU, XUEMEI CAO, XIAOQIN SHI, JIBIN LI, Chongqing, China

Objective: In human and rodents, some individuals may remain lean even challenged with high energy intake. The mechanism underlying the resistance to diet induced obesity was poorly understood. Here, we used C57BL/6J mice to establish mice models of high-fat-diet (HFD) induce obe-sity (DIO) and resistance to DIO (DIO-R) to investigate the role of gut micro-biota and brown adipose tissue (BAT) thermogenesis in the development of DIO-R.

Methods: C57BL/6J mice were randomly fed with low-fat-diet (LFD) or HFD. DIO-R was defined as those HFD fed mice with body weight lower than the average plus 3 standard deviations of LFD group after 10weeks of HFD feeding. Mice were fed the same diet for another 12 weeks. Acute cold expo-sure test was conducted in some mice before sacrificed. BAT, subcutaneous white adipose tissue (sWAT) and small intestinal mucosa were collected for histological and gene expression analysis. Bacterial DNA from cecal con-tents was extracted from mice not receiving cold exposure, and the diversity of gut microbiota was analyzed by Miseq sequencing.

Results: Under cold exposure, BAT and UCP1 mRNA levels in DIO-R mice were significantly higher than DIO; sWAT UCP1 and PGC-1α mRNA levels in DIO-R were higher than LFD and DIO. Lefse analysis of gut microbiota in LFD, DIO-R and DIO mice showed that there were differences in the composi-tion of gut microbiota; the dominant gut microbiota were Firmicutes, Pro-teobacteria, Bacteroidetes, Deferribacteres, Spirochaetes and Tenericutes; however, Bacteroidetes abundance in DIO-R mice was lower than DIO mice, while Proteobacteria abundance was higher than DIO mice; Reg3g mRNA levels in small intestinal mucosa of DIO-R were significantly higher than LFD and DIO.

Conclusion: Higher capacity for BAT thermogenesis and sWAT browning, and higher abundance of Proteobacteria in the intestine were critical con-tributors for DIO-R mice in resistance to DIO and maintaining a healthy body weight.

Supported By: National Natural Science Foundation of China (81270947, 81570763)

WITHDRAWN

A547


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—ANIMAL

2082‑PApelin‑Fc Fusion Recombinant Protein Improves Glucose Disposal in Diet‑Induced Obese MiceWEIMIN WANG, DONGMING ZHANG, RONGZE YANG, XIAOJIAN SUN, DALONG ZHU, DAWEI GONG, Nanjing, China, Baltimore, MD

Background: Apelin is a ligand peptide of the G-protein-coupled receptor APJ and exhibits a wide spectrum of activity in multiple organs and tissues. However, the short serum half-life of the apelin peptide limits in vivo biologi-cal studies.

Methods: By using an Fc fusion platform, we engineered a fusion protein of recombinant apelin-13 to IgG1 Fc. The fusion protein was purified by Pro-tein A affinity chromatography. A representative Western blot was used to show blood concentration after a single injection of recombinant Fc-apelin13 at the indicated time points in mice. Effects of Fc-apelin13 on cAMP and ERK signaling activity were measured by CRE-and SRE-driven luciferase activ-ity in CHO cells. Effects of Fc-apelin13 on glucose metabolism were investi-gated in HFD-induced obese mice.

Results: We created lentiviral constructs of an IgFc fusion protein to ape-lin-13. The purity of the engineered proteins was higher than 95% and the yield was approximately 20-40 mg/L cultured supernatant. Pharmacokinetic analysis showed the estimated half-life of Fc-apelin13 in blood is approxi-mately30 hours. The CRE-luc activity was significantly decreased whereas the SRE-luc activity was significantly increased in a dose-dependent manner after treatment with Fc-apelin13 in Reporter CHO lines co-expressing APJ/SV40-renilla with CRE-luc2p or with SRE-luc2P. 4-wk Fc-apelin13 administra-tion led to a 14% decrease of glycemia and improvement of glucose toler-ance in HFD-induced obese mice. Western immunoblot revealed that ERK1/2 phosphorylation was decreased by Fc-apelin13 in the liver tissue of mice.

Conclusions: A fusion of recombinant apelin-13 to IgG1 Fc improved the pharmacokinetic profile compared to native apelin-13 peptides. It decreased CRE-luc activity and increased SRE-luc activity in vitro and improved glucose metabolism in vivo. We expect that this fusion protein will help to elucidate the biological functions of apelin at higher efficiency and may serve as a better therapeutic candidate.

Supported By: National Institutes of Health; Maryland Diabetes Research Cen-ter; Nutrition Obesity Research Center

2083‑P

2080‑PAlteration of Bile Acid Species May Contribute to the Stronger Metabolic Improvement Seen in Roux‑en‑Y Gastric Bypass as Com‑pared with Vertical Sleeve GastrectomyRAYMOND LAU, SUNIL KUMAR, CHRISTOPHER HALL, THOMAS PALAIA, JENNY LEE, COLLIN BRATHWAITE, LOUIS RAGOLIA, Mineola, NY

Roux-en-Y gastric bypass (RYGB) and vertical sleeve gastrectomy (VSG) are popular bariatric surgery interventions. While the VSG has been an increasingly popular surgery, RYGB demonstrates to have at least slightly more potent metabolic effects on weight and type 2 diabetes (T2DM). Anec-dotally, the authors have noted this as well. Whether this relates to the dif-ferent anatomic alteration or differing biologic changes remains unclear. Bile acid related metabolism appears to have a role in the improvement through various studies and both surgeries. However, the mechanisms of how this is achieved remains unclear. We hypothesize specific components of bile acids may be responsible for this metabolic improvement and may be surgery-specific.

Methods: RYGB and VSG were performed in Zucker Diabetic Fatty (ZDF) rodents and serum samples of bile acids were obtained at 4 and 12 weeks.

Results: At 12 weeks, cholic acid levels were not found to be significantly increased in RYGB as compared to prior to surgery. Similarly, cholic acid lev-els in VSG was not elevated as compared to controls. However, chenodeoxy-cholic and glycochenodeoxycholic acid showed significant increases two to twenty fold respectively in RYGB at 4 and 12 weeks as compared to sham. Glycoursodeoxycholic acid was increased at both 4 and 12 weeks in RYGB but not significantly, although this was not observed in VSG groups.

Conclusion: Bile acid elevation in RYGB favors the improvement of specific fractionated bile acid components which may lead to stronger metabolic improvement seen in RYGB.

2081‑PEndothelial Acyl‑CoA Synthetase 1 Contributes to Diet‑Induced Obesity and Proinflammatory Response in Adipose TissueGUANG REN, TEAYOUN KIM, MARTIN E. YOUNG, ROSALIND COLEMAN, JEONG A. KIM, Birmingham, AL, Chapel Hill, NC

Vascular endothelium contributes to fuel metabolism by delivering nutri-ents and hormones to peripheral tissues. Saturated FAs (SFA) stimulate pro-inflammatory response in endothelial cells, which is associated with endo-thelial dysfunction and insulin resistance. Circulating long chain fatty acids (FA) are elevated in subjects with metabolic syndrome, and FA are transported to peripheral tissues through capillary endothelial layer. Thus, FA transport from vascular endothelium to parenchymal cells may contribute to fuel uti-lization in metabolic tissues. However, the underlying mechanism is incom-pletely understood. Majority of cytosolic long chain FA are converted to long chain fatty acyl-CoAs by long chain acyl CoA synthetases (ACSLs). Although ACSL1, among 5 mammalian ACSL isotypes, is the most extensively studied isotype in metabolic tissues, the role of ACSL1 in vascular endothelium is largely unknown. In the present study, we hypothesize that endothelial ACSL1 (e-ACSL1) contributes to diet-induced obesity (DIO) and insulin resistance by stimulating proinflammatory response in vascular endothelium. We found that inhibition of ACSLs by triacsin C attenuated SFA-induced pro-inflammatory responses in human aortic endothelial cells in vitro. Triacsin C also ameliorated palmitate-induced impairment of vasodilator action of insulin in intact vessels. Next, we generated endothelium specific ACSL1 knockout mice by breeding ACSL1f/f mice to VE-cadherin-Cre mice. Deficiency of e-ACSL1 ameliorated DIO and insulin resistance, and reduced proinflammatory responses in adipose tis-sue in high fat diet mice. From these results, we conclude that e-ACSL1 plays important roles in proinflammatory response, obesity and insulin resistance. This suggests a novel role of endothelial acyl-CoAs which may contribute to obesity-induced metabolic disorders.


WITHDRAWN

A548


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—ANIMAL

cellular process by which Mc3R modulates metabolic homeostasis remains unclear. Based on the evidence of the essential role of autophagy in meta-bolic regulations in liver, we hypothesized that the Mc3R modulates hepatic autophagy and lipid metabolism in obesity.

Methods: We examined hepatic mRNA and protein expression of factors important for lipid accumulation and autophagy in fed- and fasted homozygous knock-in mice where murine Mc3R was replaced with wild type human Mc3R (Mc3RhWT/hWT) or hypoactive “double mutant” human Mc3R (Mc3RhDM/hDM, an obesity model), Mc3R-/- mice, and C57Bl/6J controls.

Result: Mc3RhDM/hDM and Mc3R-/- mice had significantly greater total body weight and fat mass but less fat-free mass as well as increased hepatic tri-glycerides compared to Mc3RhWT/hWT. We found increased basal autophagy gene expression such as LC3 II, ATG 5 and ATG 7 in Mc3RhDM/hDM and Mc3R-/- mice, but markedly impaired induction of autophagy after 24 h fasting. Lipo-genic genes FAS and PPARγ were up-regulated, but beta-oxidative genes PPARα and CPT1α were not induced in liver of Mc3RhDM/hDM and Mc3R-/- mice compared to Mc3RhWT/hWT or BL6 mice.

Conclusion: Mc3RhDM/hDM and Mc3R-/- mice exhibit an obese phenotype with increased hepatic lipid content. This may be in part due to a defective autophagy induction and increased lipogenesis in liver.

Supported By: Eunice Kennedy Shriver National Institute of Child Health and Human Development

2087‑PHDAC Inhibition Prevents Cardiac Remodeling and Contractile Dysfunction in High‑Fat Diet‑Induced Obesity: Role of Autophagy RegulationYINGMEI ZHANG, NAN HU, JUN REN, Shanghai, China, Laramie, WY

Histone post-translational modification, mediated by histone acetyltrans-ferases and deacetylases, is one of the most studied factors affecting gene expression and is considered a promising drug target for the management of cardiovascular diseases. Cardiac complications are common in obesity including inflammation, hypertrophy, compromised energy metabolism and contractile function although a role for histone modification remains unknown. Here we examined the cardiac effects of the class I/II histone deacetylase (HDAC) inhibitor trichostatin A (TSA) in high fat diet-induced obesity. C57BL6 mice were placed on a 45% high-fat diet (HF) or a regular chow diet. Mice on HF developed much greater body weight gain compared with chow diet-fed mice at 22 weeks, manifesting impaired glucose toler-ance, insulin resistance, and dampened cardiac autophagy. Ten week treat-ment with TSA (0.3 mg/kg/every other day, i.p.) starting after 12 week of HF feeding did not reduce body weight, but it reversed insulin resistance, cardiac pro-inflammatory markers including tumor necrosis factor-α expres-sion, nuclear factor kappa B, cardiac remodeling and contractile dysfunction as assessed using echocardiography, IonOptix MyoCam and histological methods, in comparison with HF controls. TSA improved cardiac autopha-gic response which was compromised by HF diet intake. Supporting a direct mechanism of action, TSA (100 nM) prevented palmitate-induced lipotoxicity and loss of autophagy in isolated mouse cardiomyocytes in vitro. Interestingly, TSA-offered beneficial responses were negated by ablation of autophagy using Beclin-1 knockout. These data support a beneficial role for HDAC inhi-bition in HF-induced insulin resistance, inflammation, cardiac remodeling and contractile derangement possibly via an autophagy-dependent mechanism.

2088‑PIncreasing Central Dopamine to Norepinephrine Neuronal Activity Ratio Reduces Insulin Resistance (IR) and Increases White Adipose Tissue Fat OxidationMICHAEL EZROKHI, TSUNG HUANG TSAI, SCOTT WATTERS, CHRISTINE CARDI, ANTHONY H. CINCOTTA, Tiverton, RI

The peak in circadian dopaminergic activity (DA) at the biological clock area, suprachiasmatic nucleus, at daily locomotor activity onset is dimin-ished in IR states and its restoration by timed daily administration of dopa-mine agonist reduces IR in animals and humans. This dopamine effect on IR is in part via hypothalamic inhibition of elevated sympathetic tone. This study tested whether Pantethine (P), at doses that inhibit dopamine beta hydroxy-lase and thus conversion of dopamine to norepinephrine, plus the dopamine D2 receptor agonist, bromocriptine (B) may reduce IR and obesity in mice on a high fat diet (HFD) (60% calories from fat). Such mice were subsequently randomized to 1 of 4 treatment groups administered either B (10mg/kg), P (1110 mg/kg), B + P, or vehicle (V) at the onset of locomotor activity daily for 21 days while maintained on the HFD. Liver triglycerides, epididimal fat pad weight (FPW), and retroperitoneal FPW, were reduced by 51%, 65%, and 74% respectively by B + P treatment relative to V control (P<0.004). Effects

2084‑PBlood‑Brain Barrier Disruption in a Diet‑Induced Obese Model of Type 2 Diabetes: Treatment with the Mitochondrial Anhydrase Inhibitor TopiramateTHERESE S. SALAMEH, WILLIAM G. MORTELL, CASSANDRA A. DICKSON, WILLIAM A. BANKS, Seattle, WA

All forms of diabetes mellitus are characterized by chronic hyperglycemia resulting in the development of microvascular and macrovascular pathologies. Diabetes is also associated with changes in the brain microvasculature lead-ing to dysfunction and disruption of the blood-brain barrier (BBB), a specialized system of microvascular endothelial cells protecting the brain from toxic sub-stances in circulation, while permitting CNS entry of nutrients and endocrine signals using active transport mechanisms and passive diffusion. In diabetes, BBB damage is associated with increased oxidative stress (OxSt) and reac-tive oxygen species (ROS) from hyperglycemia-induced oxidative metabolism of glucose, which can be reduced with the use of a mitochondrial carbonic anhydrase inhibitor (mCAI). Previously, we demonstrated that in a streptozoto-cin (STZ)-induced mouse model of type 1 diabetes, BBB disruption occurred in five brain regions: frontal cortex, occipital cortex, parietal cortex, midbrain, and thalamus, and was attenuated using the mCAI, topiramate. Studies have implicated that dietary and metabolic factors can lead to damage of the BBB. Also, impaired transport across the BBB occurs for hormones such as leptin and ghrelin in obese animals. In this study, we examined BBB disruption in diet-induced obese (DIO) CD-1 mice fed a 60% high-fat diet for 16 weeks and demonstrated that those DIO mice who developed hyperglycemia (blood glu-cose >250 mg/dL) showed BBB disruption in the hypothalamus and hippocam-pus. DIO mice showed increased gliosis in regions developing BBB disruption. As obesity is linked to increased OxSt, treatment with the mCAI topiramate attenuated this result in the hypothalamus.

Supported By: National Institutes of Health (R21NS093368-02)

2085‑PAssociations among the Cecal Microbiome and Bacterially‑Derived Cecal Xeno‑Metabolites during Diabetes Progression in the UC Davis Type 2 Diabetes Rat ModelBRIAN D. PICCOLO, JAMES L. GRAHAM, UMESH WANKHADE, INTAWAT NOO-KAEW, KELLY E. MERCER, KARTIK SHANKAR, PETER J. HAVEL, SEAN H. ADAMS, Little Rock, AR, Davis, CA

The gut microbiome is altered in obesity and diabetes, but the molecular signals linking gut microbes and host metabolic regulation have not been established. Our aim was to identify gut microbe-derived xeno-metabolites that associate with alterations in the microbiome during the progression of a type 2 diabetes-like phenotype. Cecal contents were collected from chow-fed and age-matched male UC Davis type 2 diabetes rats before the onset of diabetes (PD, n = 15), 2 wk recently-diabetic (RD, n = 10), 3 mos (D3M n = 11) and 6 mos (D6M n = 7) post-onset of diabetes. Microbial profiles were assessed using amplicon sequencing of 16S rRNA and xeno-metabolites were assessed by LC-MS. Only p-cresol sulfate, serotonin, adenine, and inosine were significantly altered by diabetes stage (P < 0.05; ANOVA). Actinobacteria abundance decreased from early to late stages of diabetes and was positively associated with indole-3-acetic acid (in PD rats) and hydroxy-hydrocinnamic acid (in D6M rats). Bacteroidetes, Tenericutes, and Cyanobacteria were posi-tively associated with cecal 3-hydroxybenzoic acid and suberic acid in PD rats; however, negative associations were found among Tenericutes and suberic acid following diabetes onset. Bacterial diversity was positively associated with 3-hydroxybenzoic acid, p-cresol sulfate, isobutyric acid, glycylvaline, TMAO, and 2-methylbutyric acid in PD rats, but negatively associated with 3-hydroxybenzoic acid and glycylvaline in D3M and D6M rats. These associa-tions provide evidence that microbial metabolism is altered during host diabe-tes progression, even when controlling for diet, sex, strain and housing factors known to confound microbiome interpretations in rodent and human obesity and type 2 diabetes studies. The specific signals from the host that regulate xenometabolism and microbe populations remain to be elucidated.

Supported By: U.S. Department of Agriculture-Agricultural Research Service

2086‑PMelanocortin 3 Receptor Regulates Autophagy and Lipid Metabo‑lism in LiverSTEVEN B. CAI, JOO YUN JUN, POOJA G. PATEL, ANDREW J. UHLMAN, ROBIN B. ROBERSON, JACK A. YANOVSKI, North Chicago, IL, Bethesda, MD

Background: Mc3R is known to modulate metabolic homeostasis in humans and mice. We previously reported that humans with Mc3R hypo-active mutations have altered nutrient partitioning, with accumulation of triglycerides in adipose tissue and liver, developing obesity. However, the

A549


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

remission in order to direct treatment and potentially discover remission mechanisms that may be targeted in new, non-invasive treatments.

In this study we have used clinical data to predict early remission (HbA1c<6.5% and no T2D medication after 3 months) in a cohort of 170 obese T2D patients submitted to RYGB, with remission in 37%. First we used a feature selection setup to identify clinical factors important for remission. Second, these factors were applied to predict remission using an artificial neural network algorithm. After optimization of the model, validation was performed on an independent cohort of 80 obese T2D patients submitted to RYGB in the same center, with remission in 27%.

We identified 5 clinical variables related to remission including 3 previ-ously known variables (antidiabetic treatment, T2D duration, HbA1c) and 2 variables that have not previously been included in clinical models (smok-ing status, 2-hour post challenge blood glucose). The combination of these variables could predict remission in the independent cohort with high per-formance (AUROC: 0.865).

To assess the robustness and reliability of the features found, we iden-tified inconsistently assigned patients with potentially problematic initial remission labeling due to lack of standards for antidiabetic drug withdrawal after surgery. The models were then rerun after reassignment of remission status for these patients.

This study contributes both to a better understanding of the mechanisms underlying early remission of diabetes following RYGB and also proposes avenues for improving algorithms for clinical decision making.

Supported By: European Union Seventh Framework Programme (FP7/2007-2013); European Federation of Pharmaceutical Industries and Associations

& 2091‑PPostprandial Glucose Tolerance, Glycaemic Control, and Body Weight in Obese Patients With and Without Type 2 Diabetes Treated with Duodenal‑Jejunal Bypass Sleeve for 52 WeeksTINA JORSAL, ULRICH ROHDE, PETER VILMANN, EBBE LANGHOLZ, STEFFEN U. FRIIS, CECILIE A. FEDERSPIEL, JENS JUUL HOLST, TINA VILSBØLL, FILIP K. KNOP, Copenhagen, Denmark, Hellerup, Denmark, Herlev, Denmark

The endoscopically implantable and reversible duodenal-jejunal bypass sleeve, the EndoBarrier Gastrointestinal Liner®, results in weight loss and has been reported to improve glycaemic control in type 2 diabetes (T2D). We investigated the long-term effect of the EndoBarrier on postprandial glucose tolerance and insulin levels, glycaemic control and body weight. Six normal glucose tolerant (NGT) persons (age (median with range in brack-ets): 51.5 (27-60) years, body weight (BW): 100.0 (92.7-115.5) kg, body mass index (BMI): 33.7 (30.3-36.8) kg/m2, glycated haemoglobin (HbA1c) 31 (29-43) mmol/mol)) and nine metformin-treated patients with T2D (age: 50 (40-67), BW: 103.7 (80.9-131.9) kg, BMI: 38.6 (31.6-40.5) kg/m2, HbA1c: 50 (32-77) mmol/mol)) underwent a 4-hour mixed liquid meal test before (baseline) and 52 weeks (52w) after implantation and again four weeks after explantation (4wE). At 52w, NGT and T2D subjects had lost 9.6 (2.4-15.2) and 7.6 (-0.4-21.2) kg, respectively. At 4wE, NGT persons had regained 0.7 (-0.8-3.3) and T2D patients 1.5 (-0.9-3.4) kg, respectively. HbA1c remained unaffected in both groups throughout the trial. Plasma levels of fasting and postprandial glucose, insulin and C-peptide did not differ between baseline and 52w, and did not deteriorate at the 4wE study day within any of the groups. Met-formin doses remained unaltered from baseline to 4wE. EndoBarrier treat-ment results in moderate body weight loss in obese persons with NGT and patients with T2D, but long-term improvements in HbA1c, fasting plasma glu-cose and postprandial glucose tolerance were not observed in our patients with type 2 diabetes.

& 2092‑PGastric Bypass Biliopancreatic Limb Length Influences Meal‑Related Hormone Response and Diabetes RemissionBÁRBARA G. PATRÍCIO, JOANA MONTEIRO, TIAGO MORAIS, MARTA GUI-MARÃES, SIMON VEEDFALD, SOFIA S. PEREIRA, BOLETTE HARTMANN, JENS J. HOLST, MÁRIO NORA, MARIANA P. MONTEIRO, Porto, Portugal, Copenhagen, Denmark

Roux-en-Y gastric bypass (RYGB) is associated with long-term weight-loss and a high rate of type 2 diabetes (T2D) remission. It has been suggested that minor modifications of the surgical technique could result in improved metabolic outcomes. Our aim was to access the influence of the RYGB bilio-pancreatic limb (BPL) length in the meal related gastro-intestinal hormone response and T2D improvement. A cohort of T2D obese patients (n=114) submitted to classical BPL (n=41; BPL length 84±2 cm) or long BPL (n=73; BPL=200 cm) RYGB were followed-up to 5 years’ after surgery, while peri-odically monitored for weight loss and metabolic parameters. After weight

of such magnitude were not observed with B or P and not accounted for by food intake changes. In a second similar study, B + P treatment reduced epi-didimal FPW by 50% (from 2.1 ± 0.2 to 1.1 ± 0.1 g, P<0.0001), retroperitoneal FPW by 49% (1.2 ± 0.2 to 0.6± 0.1 g, P=0.01), plasma glucose by 43% (216 ± 5 to 123 ± 4 mg/dl) (P<0.0001), plasma insulin by 71% (5.3 ± 1.1 to 1.5 ± 0.4 ng/ml, P=0.02), and HOMA-IR by 83% (81 ± 17 to 14 ± 3 mmol/L*mIU/L, P<0.01. In a third similar study, B + P treatment of such IR syndrome mice increased epididimal adipose tissue basal oxygen consumption by 48% (16.4 ± 1.0 to 24.3 ± 0.6 pmol/min/mg, P<0.0001), endogenous free fatty acid oxidation (FFAO) by 67% (6.9 ± 1.0 to 11.6 ± 0.9 pmol/min/mg, P<0.01), and exogenous FFAO by 134% (2.8 ± 0.7 to 6.5 ± 1.3 pmol/min/mg, P<0.05). Circadian timed daily treatment with B + P combination produces marked improvements in IR, plasma glucose, adipose FPW, and adipose fat oxidation.

OBESITY—HUMAN

Moderated Poster Discussion: Human Obesity and Diabetes—Effects of Bariatric Procedures (Posters: 2089-P to 2094-P), see page 17.

& 2089‑PAssociation of Malabsorptive Bariatric Surgery (Biliopancreatic Diversion) and Long‑Term Survival in Obese Diabetic and Nondia‑betic PatientsANTONIO E. PONTIROLI, VALERIO CERIANI, GIULIANO SARRO, AHMED ZAKARIA, FRANCESCO CETTA, MARCO FANCHINI, ALBERTO MORABITO, Milan, Italy, Magenta, Italy

Bariatric surgery (gastric banding and gastric bypass) is associated with higher long-term survival than routine medical treatment. In spite of the fact that biliopancreatic diversion (BPD) is probably the most effective bariat-ric procedure in terms of resolution of co-morbidities, no data is available on long-term survival in obese patients undergoing BPD. Aim of this study was to compare long-term survival in obese patients undergoing BPD and in controls receiving routine medical treatment. 1533 obese patients of the Lumbardy Region, Italy, BMI 35-76 kg/m2, undergoing BPD (n=292, 68 men/224 women, 72 with diabetes) or receiving medical treatment (n=1,241, 450 men/91 women, 410 with diabetes) during the period 2002-2008 (visit 1), were evaluated. Identification codes of patients were entered in the Ital-ian National Health System Lumbardy database, that contains life status and causes of death. Survival at December 31, 2015 was compared across BPD patients and controls using Kaplan-Meier plots Cox regression analyses. The observation period (mean ±SD) was 9.7 ± 2.59 years (1.5 to 13.7 years). BPD was associated with lower mortality (HR=0.49, 95% C.I. 0.32-0.76, p=0.001); since patients undergoing BPD were younger and with lower blood pressure levels, group matching of controls was made for blood pressure (BPD: n as above; medical treatment: n=826, 210 men/328 women, 263 with diabetes); HR was 0.33, 95% C.I. 0.21-0.52, p=0.001); group matching was made also for age (medical treatment: n=588, 113 men/183 women, 117 with diabetes); HR was 0.53, 95% C.I. 0.32-0.88, p=0.015). Reduction of mortality was always similar for patients with and without diabetes. These data indicate that BPD is associated with lower mortality compared to medical treatment. Studies are needed to evaluate long-term survival in patients undergoing other surgi-cal techniques such as biliointestinal bypass and sleeve gastrectomy.

& 2090‑PMachine‑Learning Algorithm Predicts Early Type 2 Diabetes Remis‑sion following Roux‑en‑Y Gastric BypassCECILIA E. THOMAS, VIOLETA RAVERDI, HELLE KROGH PEDERSEN, JOHANN GASSENHUBER, CAROLINE BRORSSON, VALBORG GUDMUNDSDOTTIR, ANA VIÑUELA, CEDRIC HOWALD, HAN WU, KARINA BANASIK, LOÏC YENGO, MARK HAID, MELISSA K. THOMAS, MICHAELA HINTERHOLZER, MICKAËL CANOUIL, MUN GWAN HONG, PETER DAVIDSEN, RAMNEEK GUPTA, SAPNA SHARMA, SIMONE WAHL, EMMANOUIL T. DERMITZAKIS, HARALD GRALLERT, JOCHEN M. SCHWENK, MARK FARMEN, SØREN BRUNAK, FRANÇOIS PATTOU, THE DIRECT CONSORTIUM, Copenhagen, Denmark, Lille, France, Kongens Lyngby, Denmark, Frankfurt, Germany, Geneva, Switzerland, Indianapolis, IN, Neuherberg, Germany, Solna, Sweden

Roux-en-Y gastric bypass (RYGB) can be an effective treatment in severely obese patients with type 2 diabetes (T2D). While some patients reach ade-quate glycemic control within a few months after surgery, others still require antidiabetic treatment following surgery. It is thus valuable to be able to predict surgical remission of T2D and to understand the mechanisms of early

A550


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

Results: Following bariatric surgery, subjects showed a reduction in BMI (49.6±1.8 vs. 37.5±1.7 vs. 34.4±1.2, P<0.0001), HbA1c (57.3±3.4 vs. 41.2±2.9 vs. 38.4±1.9 mmol/mol, P<0.0001), systolic (135.7±3.3 vs. 121.9±3.8 vs. 118.7±3.5 mmHg, P=0.002) and diastolic (73.6±3.6 vs. 66.6±2.9 vs. 69.0±2.6 mmHg, P=0.008) blood pressure at 6 and 12 months after bariatric surgery. There was a significant and progressive improvement in NSP (4.6±0.9 vs. 2.7±1.1 vs. 0.7±0.3, P=0.001), NDS (2.1±0.4 vs. 2.9±0.8 vs. 1.4±0.6, P=0.02), CNFD (24.2±1.4 vs. 25.5±2.3 vs. 28.1±1.3 no./mm2, P=0.019), CNBD (34.1±3.5 vs. 39.5±4.7 vs. 42.3±3.7 no./mm2, P=0.048) and CNFL (14.9±0.8 vs. 16.4±1.0 vs. 16.9±0.7 mm/mm2, P<0.009).

Conclusion: Bariatric surgery leads to an improvement in symptoms and small nerve fibre structure, which can be identified using CCM as early as 6 months after surgery.

Figure.

Moderated Poster Discussion: Human Obesity—Central and Peripheral Mechanisms (Posters: 2095-P to 2100-P), see page 21.

& 2095‑PAdipose Tissue Remodeling following Eight‑Week Calorie Restric‑tion or Intermittent Fasting in Females Who Are Overweight and ObeseBO LIU, AMY T. HUTCHISON, CAMPBELL H. THOMPSON, GARY A. WITTERT, LEONIE HEILBRONN, Adelaide, Australia

Background: Macrophage recruitment to adipose tissue (AT) and tissue remodeling occur in response to nutrient availability. This study is the first to compare the effects of daily moderate calorie restriction (CR) vs. intermit-tent fasting (IF) on macrophage recruitment and AT remodeling in humans.

Methods: Women (N=75, 50.3±1.0 y, BMI 32.4±0.5 kg/m2) were random-ized to CR70, IF70 and IF100 group for 8 weeks. CR70 participants consumed similar amount of food daily, whereas IF individuals ate breakfast, prior to initiating a 24-hour fast, for 3 non-consecutive days/week. Food were pro-vided to meet 70% (IF70 and CR70), or 100% (IF100) of calculated energy requirements. Fasting bloods and subcutaneous AT biopsies were obtained at baseline, and 8 weeks, after a 12 h overnight fast (all groups), and 24 h fast (IF groups). Monocyte chemotactic marker (CCL2), markers of pan- (CD68), M1- (CD40), M2- (CD163) macrophages, extracellular matrix (COL6A1, MMP2 and TIMP1) and lipolysis (LIPE and PLIN1) were examined by qPCR. Fat cell size and macrophage numbers were assessed by immunohistochemical staining.

Results: Slightly greater weight loss was observed in IF70 (5.4±0.5) vs. CR70 (3.9±0.4) vs. IF100 (2.7±0.5 kg, all P<0.01), after 8 weeks. Non-ester-ified fatty acids were reduced more in IF70 vs. CR70 after a 12 h fast, and increased after 24 h fasts in IF groups (P<0.05). Fat cell size was reduced in all groups (P<0.05). Macrophage markers did not change in CR70 group. However, pan- and M1-macrophage numbers were increased after a 24 h fast in IF groups. CCL2, CD40 and LIPE expression were increased after a 24 h fast in IF70 only (P<0.05). MMP2 which degrades extracellular matrix was increased in CR70 and IF70 (P<0.05).

Conclusions: The mode of dietary restriction resulted in distinct differ-ences in AT remodeling. The increase in macrophage infiltration in response to severe energy deprivation may be an appropriate response to the increased lipolysis and AT remodeling.

Supported By: Australian National Health and Medical Research Council; Aus-tralian Research Council; Diabetes Australia; Royal Adelaide Hospital

loss stabilization, mixed-meal tests were performed on a subset of non-T2D patients submitted to classical BPL (n=9) or long BPL (n=11) RYGB, while blood was sampled before and timely after the meal for glucose, insulin, C-peptide, total GLP-1, glucagon, GIP, PYY and PP measurement. At 5 years after surgery, T2D remission rate was significantly higher in patients submit-ted to long BPL RYGB (73.1% vs. 55%, p<0.05), with a lower relapse rate (11.9% vs. 32%, p<0.05) and an improved metabolic control with decreased need for pharmacological treatment in those patients with persistent dis-ease (p<0.05). After a mix meal test both patient groups depicted similar glucose excursion curves, although those submitted to long BPL RYGB dis-played higher GLP-1 levels at t=45 min (p<0.05) with a higher AUC (p=0.01), lower GIP levels at t=15 min (p<0.01), as well as lower insulin and C-peptide levels at t=30 min (p<0,001), when compared the classical BPL RYGB group. Modification of the RYGB procedure by increasing the BPL length prompts an increased meal elicited GLP-1 response and enhances T2D remission rate. This data suggests that RYGB surgical technique could be tailored to elicit a personalized endocrine profile to promote additional metabolic benefits for diabetic patients submitted to bariatric surgery.

Supported By: Fundação para a Ciência e a Tecnologia (PEst-OE/SAU/UI0215/2014)

& 2093‑PGut Hormone FGF‑19 Modulates Adipose Mitochondrial Function and Type 2 Diabetes Recovery following Bariatric SurgeryLUCIA MARTINEZ DE LA ESCALERA, IOANNIS KYROU, JANA VRBIKOVA, VOJTECH HAINER, PETRA SRAMKOVA, MARTIN FRIED, MILAN K. PIYA, SUD-HESH KUMAR, GYANENDRA TRIPATHI, PHILIP G. MCTERNAN, Coventry, United Kingdom, Birmingham, United Kingdom, Prague, Czech Republic, London, United Kingdom

Background: Fibroblast growth factor-19 (FGF-19) is a novel enterokine regulator of glucose and lipid homeostasis, and in mice, necessary for weight loss and type 2 diabetes recovery after bariatric surgery. In humans, we investigated the effect of different bariatric procedures on circulating FGF-19 levels and the resulting impact on white adipose tissue (AT) mito-chondrial health.

Methods: Obese and type 2 diabetic women (n=39, BMI>35 Kg/m2) under-going either bilio-pancreatic diversion (BPD), laparoscopic greater curvature plication (LGCP), or laparoscopic adjustable gastric banding (LAGB) partici-pated in this ethics approved study. Anthropometry, biochemical, clinical data, serum, and AT biopsies were collected before and 6 months after sur-gery for assessment of mitochondrial number, gene expression and circulat-ing FGF-19 levels.

Results: Circulating FGF-19 was inversely correlated with AT mitochon-drial number across all surgeries (n=39). Serum FGF-19 levels increased in both BPD and LGCP (χ2(2)=8.088; p=0.018); but decreased after LAGB (p=0.028). Type 2 diabetic outcomes mirrored circulating FGF-19 levels, with BPD and LGCP producing similar and more profound HbA1c (↓28%) reduc-tion (adjusted for BMI) compared with LAGB. Unique to BPD, mitochondrial number corresponded directly with changes in 12 of 14 mitochondrial genes assayed (p<0.01), which was accompanied by greater weight loss (↓30%) and lowering of serum cholesterol (↓25%).

Conclusions: Elevated serum FGF-19 levels post-surgery were associ-ated with improved mitochondrial health in AT and overall diabetic remis-sion. Changes in circulating FGF-19 levels were surgery-specific, with BPD producing the best metabolic outcomes among the studied operations (BPD>LGCP>LAGB), and highlight mitochondria in AT as a potential target of FGF-19 during diabetes remission.

Supported By: European Society for the Study of Diabetes; National Council for Science and Technology of Mexico (313802)

& 2094‑PBariatric Surgery Improves Neuropathic Symptoms, Deficits, and Corneal Nerve Morphology in Obese Patients with DiabetesSHAZLI AZMI, UAZMAN ALAM, MARYAM FERDOUSI, GEORGIOS PONIRAKIS, IOANNIS N. PETROPOULOS, JONATHAN SCHOFIELD, TARZA SIAH MANSUR, ANDREW MARSHALL, BASIL AMMORI, HANDREAN SORAN, RAYAZ A. MALIK, Manchester, United Kingdom, Doha, Qatar

Introduction: Whilst bariatric surgery can lead to remission of type 2 dia-betes, the effect on microvascular complications, in particular neuropathy is unclear.

Methods: 25 morbidly obese patients undergoing bariatric surgery under-went a comprehensive neuropathy assessment at baseline, 6 and 12 months post-surgery.

A551


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

& 2098‑PAn Epigenome‑Wide Study to Identify DNA Methylation that Asso‑ciates with ObesityPENG CHEN, PAOLO PIAGGI, SAYUKO KOBES, CLIFTON BOGARDUS, III, ROBERT L. HANSON, LESLIE J. BAIER, Phoenix, AZ

Obesity is a chronic disease which is often accompanied by low-grade inflammation. Epigenetic association studies have identified cytosine-phos-phate-guanine (CpG) sites at which differential DNA methylation, which can affect gene expression, associates with obesity as measured by BMI. However, the extent to which these associations transfer to diverse popu-lations, such as American Indians who have a high prevalence of obesity, remains unclear. In the current study, we conducted a genome-wide analysis to identify CpG sites at which methylation associates with BMI in Pima Indi-ans. DNA methylation was measured on the Illumina Infinium HumanMeth-ylation450 BeadChip. We analyzed 423,311 CpG sites in peripheral blood leukocyte samples from 399 nondiabetic Pima Indians (mean [± SD] age = 13.1±5.9 years). BMI (measured at the time of blood sampling) was natural logarithm transformed and tested for association with DNA methylation with adjustments for sex, age, batch effect and other appropriate covari-ates. CpG sites of genome-wide significance in the discovery cohort (FDR p ≤0.05) were analyzed for replication in two existing datasets of diabetic Pima Indians (N = 320, age = 35.5±11.3; N = 183, age = 53.6±11.9). Among 263 CpG sites that associated with BMI in the discovery cohort, 9 replicated in both replication cohorts (p ≤0.05 and consistent direction of effect). These were located in 6 genes and 2 enhancer elements. Three of these CpG sites map to genes (AHRR, RPS6KA2 and LGALS3BP) where DNA methylation has previously been reported to associate with BMI in other populations. The epigenetic associations at the remaining genes (DUSP5, RRAS2, APOBR) and enhancer elements are novel. Several of these genes have known roles in inflammation (DUSP5, LGALS3BP, APOBR, RPS6KA2) or cell proliferation (RRAS2 and AHRR). Thus, the present study has validated that DNA methyla-tion at some genes associates with obesity in different ethnic groups, and it identifies other genes that may have a larger effect in American Indians.


& 2099‑PEffect of Adiposity on miRNA Expression in Subcutaneous Fat Is Cell‑Type SpecificJEANIE B. TRYGGESTAD, APRIL M. TEAGUE, STEVEN D. CHERANUSEK, Oklahoma City, OK

MicroRNA (miRNA) are small, non-coding RNAs that bind to complemen-tary sequences within the 3’ untranslated region of mRNAs modulating protein production, typically degrading or repressing translation of targeted mRNAs. A recent study has shown that several miRNAs are differentially expressed in subcutaneous adipose from obese individuals, but the adipose tissue was sampled as a whole. Here we examine miRNA expression in adi-pocytes and the macrophage-rich stromal vascular fraction (SVF) of adipose tissue as well as peripheral blood mononuclear cells from 10 normal weight and 6 obese (BMI ≥ 30) young adults in order to dissect out the effect of adiposity on these specific cell types. Seven miRNA species were selected from literature as differentially expressed in adipose tissue (miR-210, miR-30a, miR-125b, and miR-199a), or were reported to be altered by exposure to diabetic conditions (miR-130b, miR-155 and miR-214). Subcutaneous adipose tissue was sampled via liposuction technique from the abdomen, microscopy was used to determine cell count and characteristics, and miRNA abundance measured by qPCR. There were no differences in SVF cell count, peripheral blood mononuclear cell (PBMC) count, adipocyte area, or adipocyte volume between the two groups. miR-130b expression was increased 1.8-fold in the SVF and 4.3-fold the isolated adipocytes of the obese subjects compared to controls (p = 0.007 and p = 0.02, respectively). The abundance of miR-155 and miR-210 was also increased in the SVF of the obese subjects by 6.7-fold and 2.9-fold (p = 0.002 and p = 0.013 respectively), but not in the homologous PBMC. These data indicate that in the face of increasing adiposity, adipose tissue miRNAs are influenced in a cell-type specific fashion. Future work is needed to understand the mechanisms that impact the differential expres-sion of miRNAs within the different cells of adipose tissue as well as the impact of the differentially expressed miRNAs on their targets and down-stream signaling mechanisms.

& 2096‑PTreg Abundance and Adipocyte Gene Expression in Human Adipose TissueDAVID BRADLEY, JOEY Z. LIU, STEPHEN BERGIN, ALECIA BLASZCZAK, ANA-HITA JALILVAND, VALERIE WRIGHT, BRADLEY NEEDLEMAN, SABRENA NORIA, WILLA A. HSUEH, Columbus, OH

Not merely a storage depot for excess caloric intake, adipose tissue (AT) is now recognized as a major source of inflammation with its immune microen-vironment driving obesity-related comorbidities. A unique population of AT regulatory T cells (Tregs) are present in lean mice, but substantially reduced in obese mice due, as we have previously demonstrated, to increased adi-pocyte activity of the major histocompatibility type 2 (MHCII) pathway. Adoptive transfer of Tregs protects against inflammation and insulin resis-tance underscoring the importance of these cells to metabolism. However, what regulates human AT Tregs is unknown. We obtained visceral AT (VAT) and subcutaneous AT (SAT) biopsies from obese (n=192, BMI 48 ± 9 kg/m2) and lean (n=36, BMI 23 ± 2 kg/m2) patients during elective surgery. Adipo-cytes were isolated for gene expression and the stromal vascular fraction was subject to flow analysis. Tregs as % of CD4+ cells were dramatically increased in lean vs. obese VAT (19 ± 17% vs. 4 ± 3%; p<0.01) and SAT (22 ± 15% vs. 7 ± 4%, p<0.01) and were negatively correlated with BMI and insu-lin resistance. In contrast, VAT or SAT CD4+ Th1 or Th2 cells did not differ. Obese vs. lean adipocytes expressed significantly higher CIITA, CD74 and HLADPA1, all prominent MHCII proteins, (p<0.02). VAT Tregs inversely corre-lated with CIITA and directly correlated with ACADm, a fatty acid oxidation gene, independent of BMI, but not with adipokine expression. In fact, CIITA and CD74 gene expression were inversely correlated with multiple adipocyte mitochondrial function genes (ATP5A, CPT1B, PGC1a, and CIDEA), ACADM, and fatty acid synthesis genes (ACC2, DGAT, and FASN). CD74 also predicted % excess body weight loss 6 mo post-bariatric surgery (r= +0.41, p<0.01). These results suggest critical changes in AT Tregs in humans are influenced by adipocyte MHCII and fatty acid metabolism/mitochondrial function, and that these pathways provide novel targets to increase AT Tregs, reduce inflammation, and attenuate obesity-induced co-morbidities.

Supported By: American Diabetes Association (1-16-ICTS-049 to W.A.H.)

& 2097‑PEffects of Deep Transcranial Magnetic Stimulation on Body Tem‑perature in ObesityANNA FERRULLI, VERONICA REDAELLI, FABIO LUZI, MICHELA ADAMO, ELENA COSTA, STEFANO PAINI, LIVIO LUZI, San Donato Milanese, Italy, Milan, Italy

Obesity is associated with increased heat production. To maintain nor-mothermia, extremities heat dissipation increases, whereas central sites heat reduces. Several mechanisms associated with obesity could induce body Temperature (T) to increase. Deep Transcranial Magnetic Stimulation (dTMS) proved to be effective in reducing body weight, acting on neuro-physiological mechanisms that underlie obesity (ADA 2016).

Aim of this study was to investigate the influence of dTMS on body T in obesity. Fourteen obese subjects (3 M, 11 F; 45.0 ± 9.5 years; BMI 38.6 ± 5.1) were randomized into 3 groups receiving 15 sessions (3 per week for 5 weeks) of high-frequency (18 Hz), low-frequency (1 Hz) or sham stimulation. Under thermoneutral conditions, the T of fingernail-bed of both hands and that of abdominal skin was measured using infrared thermography (AVIO TVS700, 320x240 pixel, spatial resolution 1.4 mrad, T resolution 0.08°C). After 5 weeks, a significant reduction of body weight was found in 18 Hz group (-3.7 ± 2.8%, p<0.05). After a single dTMS session, the fingernail-bed T of both hands significantly decreased (-5.2 ± 4.4%, p<0.05). An increase in abdominal skin T was observed in the dTMS groups compared to sham (p<0.01). Concurrently, a significant reduction of leptin (-19.5 ± 11%, p=0.05), TSH (-26.9 ± 11.5%, p<0.01), prolactin (-37.4 ± 11.3%, p<0.01), ACTH (-39.7 ± 20.4%, p<0.05), and an increase of epinephrine (+28.4 ± 26.7%, p<0.05) were found after a single 18 Hz dTMS session. Chronically, 1 Hz dTMS was found to be effective in reducing fingernail-bed T of both hands (-5.8 ± 4.3%, p<0.05). Systolic pressure decreased compared to baseline in the 18 Hz group after 4 weeks of treatment (p<0.05).

Deep TMS revealed to be effective in modulating body T, reversing obe-sity-induced alterations in heat production and dissipation. Body weight loss associated with reduction of pituitary hormones release, adipokine and sympathetic activity modulation are potential mechanisms via which dTMS exerts its modulatory action.

Supported By: Italian Ministry of Health

A552


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

vascular risk factors. We aimed to determine the relationship between NC and body fat content and distribution as well as the efficacy of NC for iden-tifying visceral adiposity and metabolic disorders. A total of 1,943 subjects (783 men, 1,160 women) with a mean age of 57.9±7.3 years were enrolled in this cross-sectional study. Metabolic syndrome (MetS) was defined accord-ing to the standard in the 2013 China Guideline. Analyses were conducted to determine optimal NC cutoff points for visceral adiposity quantified by mag-netic resonance imaging, and to compare the performance of NC with that of waist circumference (WC) in identifying abdominal obesity and metabolic disorders. The mean levels of NC for men were greater than that for women [38.0 (36.5-39.5 cm) vs. 33.6 (32.2-35.0 cm), P<0001]. Visceral fat content was independently correlated with NC. Receiver operating characteristic curves showed that the area under the curve for the ability of NC to deter-mine visceral adiposity was 0.781 for men and 0.777 for women. Moreover, in men a NC value of 38.5 cm had a sensitivity of 56.1% and specificity of 83.5%, and in women, a NC value of 34.5 cm had a sensitivity of 58.1% and specificity of 82.5%. These values were the optimal cutoffs for identifying visceral obesity. There were no statistically significant differences between the proportions of MetS and its components identified by an increased NC and increased WC (≥90.0 cm for Chinese men and ≥85.0 cm for Chinese women). The optimal cutoff points for NC to estimate MetS were 38.5 cm for men and 34.5 cm for women. NC has the same power as WC for identifying metabolic disorders in a Chinese population.

Supported By: National Basic Research Program of China (2013CB530606); Shanghai Health and Family Planning Commission (2013ZYJB1001); Shanghai Jiao Tong University (15ZH2010, 15ZH4006)

2103‑PWeight Regain in Patients with Symptoms of Post‑Bariatric Surgery HypoglycemiaCLARE LEE, SANSKRITI VARMA, JEANNE CLARK, THOMAS MAGNUSON, MICHAEL SCHWEITZER, KIMBERLEY STEELE, TODD BROWN, Baltimore, MD

Weight regain and symptoms of postprandial hypoglycemia have been observed in a subset of post-bariatric surgery (PBS) patients. Hypoglyce-mic symptoms may be an important driver of increased caloric intake in PBS patients, thus contributing to weight regain (WR). This study aimed to deter-mine whether PBS patients with hypoglycemic symptoms are at increased risk for weight regain. Patients who underwent Roux-en-Y gastric bypass (RYGB) or vertical sleeve gastrectomy (VSG) at the Johns Hopkins Center for Bariatric Surgery from Aug 2008-Aug 2012 were mailed a survey, from which weight trajectory and hypoglycemic symptoms were assessed. Percent WR was calculated as 100x (current weight (wt)-nadir wt)/(preop wt-nadir wt) and compared between dates of survey completion and postoperative year 1. Multivariable logistic regression was used. Of 428 respondents, WR was observed in 79.2% (N=339), while 20.8% (N=89) had no WR or weight loss at a mean of 29 ± 14 months. Those who had WR showed median WR of 10.8% (interquartile range (IQR) 5.6, 19.4). Compared to those who did not regain, patients with WR over 5.6% were more likely to report PBS hypoglycemic symptoms (OR=1.73, 95% CI 1.05-2.86), less likely to adhere to nutritional guidance (OR= 0.43, 95% CI 0.28-0.68), and reported longer time since post-operative year 1 (OR=1.06, 95% CI 1.05-1.08). Age, gender, race, surgery type, pre-existing diabetes, preoperative BMI, and maximum postsurgical weight loss were not significantly associated with WR. Weight regain was common in PBS patients with hypoglycemic symptoms, and in those who reported longer time since surgery and lower dietary adherence. Further studies are warranted to elucidate the role of hypoglycemia among other risk factors in PBS weight regain.

2104‑PIntermittent Hypoxia Increased Proopiomelanocortin (POMC) and Cocaine‑ and Amphetamine‑Regulated Transcript (CART) mRNAs via GATA‑1 Binding to the Promoters in Human Neuronal CellsRYOGO SHOBATAKE, KEN TAKASAWA, HIROYO OTA, ASAKO ITAYA-HIRONAKA, AKIYO YAMAUCHI, SUMIYO SAKURAMOTO-TSUCHIDA, TOMOKO UCHIYAMA, MAI MAKINO, KAZUMA SUGIE, SATOSHI UENO, SHIN TAKASAWA, Kashihara, Japan, Miyazaki, Japan

Sleep apnea syndrome (SAS) is characterized by intermittent hypoxia (IH). SAS, obesity and type 2 diabetes are strongly related with each other. In the present study, using human neuronal cells and an in vitro IH system, we investigated the direct impact of IH on the expression of major appetite regulatory genes. We exposed NB-1, SH-SY5Y and SK-N-SH cells to IH (64 cycles of 5 min hypoxia (1% O2) and 10 min normoxia (21% O2)), to normoxia, or to sustained hypoxia for 24 hours, and measured the mRNA levels of proo-piomelanocortin (POMC), cocaine- and amphetamine-regulated transcript

& 2100‑PBrain Reactivity to Food Cues Is Positively Related to Insulin Resis‑tance and Negatively Related to Dietary Restraint and Habitual Physical Activity: A PREVIEW StudyMATHIJS DRUMMEN, ANNE RABEN, MARGRIET WESTERTERP-PLANTENGA, TANJA ADAM, Maastricht, Netherlands, Copenhagen, Denmark

Differences in food reward-related brain activation comparing lean and obese individuals may contribute to overeating and the persistence of over-weight. The respective contribution of peripheral factors including physiol-ogy, anthropometry, or lifestyle factors to the observed differences is not fully explored. In this study, we investigated the impact of insulin resistance, weight status, and lifestyle factors to brain reward activation in response to visual food cues in a sub-population of the PREVIEW study, a multicenter study to determine effective lifestyle factors in T2D prevention.

In 39 obese, prediabetic subjects (m22/f17; BMI: 32.3±0.6 kg/m2; fasting glucose: 6.3±0.1 mmol/l; fasting insulin: 13.6±1.0 mU/l; HOMA-IR: 3.9±0.3) brain reward activity was assessed by functional magnetic resonance imag-ing while viewing blocks of food and non-food images. Brain activation (food vs. non-food) was extracted in a priori defined food reward regions-of-inter-est (ROIs). Contribution of eating behavior (TFEQ), habitual physical activity (Baecke), HOMA-IR, BMI or body fat percentage were determined utilizing multiple regression analysis.

In the nucleus accumbens (R2=0.3; p=0.003), insula (R2=0.3; p=0.010), prefrontal cortex (R2=0.3; p=0.015) and putamen (R2=0.2; p=0.034), brain activation was predicted by HOMA-IR, independent of BMI and body fat per-centage (P<0.05). Brain activation was inversely related to restraint scores and habitual activity in multiple ROIs, after adjusting for HOMA-IR, BMI and body fat percentage (P<0.05).

Individuals with increased peripheral insulin resistance showed more activity to food cues in brain reward regions, independent of BMI and body fat percentage. Both dietary restraint and habitual physical activity appear to be associated with decreased reactivity to food cues in brain reward regions, independent of insulin resistance, BMI or body fat percentage.

Supported By: European Union Seventh Framework Programme (312057)

2101‑PAssociations of Serum Lipocalin‑2 Levels with Total Body Fat and Visceral Fat Area in Chinese MenYUQI LUO, XIAOJING MA, XIAOPING PAN, YITING XU, QIN XIONG, YUNFENG XIAO, YUQIAN BAO, WEIPING JIA, Shanghai, China

Serum lipocalin-2 (LCN2) plays an important role in the regulation of the obesity-associated dysmetabolic state and cardiovascular disease. How-ever, relatively little is known about the relationship between serum LCN2 levels and body fat content and distribution. We examined the associations of total body fat content and abdominal fat distribution with serum LCN2 levels in Chinese men. The study was based on a cross-sectional analysis of data for 1,203 Chinese men aged 22-78 years from the Shanghai Obesity Study. Body fat percentage (fat %) was assessed by bioelectrical imped-ance analysis, and magnetic resonance imaging was adopted to quantify the visceral fat area (VFA) and subcutaneous fat area (SFA). Serum levels of LCN2 were measured with a standard enzyme-linked immunosorbent assay method. Subjects with a high fat % had higher serum LCN2 levels than those with a normal fat % regardless of their body mass index category (<25 and ≥25 kg/m2). The frequency of isolated high VFA was increased with increas-ing quintiles of serum LCN2 levels (P < 0.001), but the frequency of isolated high SFA did not differ between quintiles of serum LCN2 levels. A trend of increasing VFA was observed with increasing serum LCN2 levels (P < 0.001). Multiple stepwise regression analysis showed that VFA was positively asso-ciated with serum LCN2 levels, independent of overall obesity and other con-founding factors (standardized β = 0.082, P = 0.008). Serum LCN2 levels are positively correlated with body fat content and independently associated with VFA in Chinese men.

Supported By: National Basic Research Program of China (2013CB530606); Shanghai Health and Family Planning Commission (2013ZYJB1001); Shanghai Jiao Tong University (15ZH2010, 15ZH4006)

2102‑PNeck Circumference as an Effective Measure for Identifying Car‑diometabolic Syndrome: A Comparison with Waist CircumferenceBAO YUQIAN, YUQI LUO, XIAOJING MA, YUN SHEN, YITING XU, QIN XIONG, XUELI ZHANG, YUNFENG XIAO, WEIPING JIA, Shanghai, China

As a new anthropometric index for estimating obesity, neck circumference (NC) has been proven to be closely associated with obesity-related cardio-

A553


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

litus (T2DM) conditions becomes dysregulated. Whilst weight loss can restore this functionality, bariatric surgery can have a specific impact due to mechanical changes on gut/liver physiology. We aimed to analyse the effects of different bariatric surgeries: sleeve gastrectomy (SG), laparo-scopic adjusted gastric banding (LAGB) and biliopancreatic diversion (BPD), on changes in FGF-19 and FGF-21 levels.

Methods: Obese and T2DM women (n=41 BMI>35 Kg/m2) undergoing SG (n=14), LABG (n=13), and BPD (n=14) participated in an ethics approved study. Anthropometry, biochemical data, and adipose tissue (AT) biopsies were collected before and 6 months after surgery. FGF-19, FGF-21 levels and AT inflammation (TLR2, MYD88, TRAF6, IKK and NFkb) was assessed.

Results: Post-surgery SG led to 63% reduction in FGF-21 whilst LABG and BPD led to 41% and 4% decrease respectively. There was a significant dif-ference in FGF-21 levels between SG and BPD (p=0.021). Moreover, FGF-21 change in SG positively correlated with changes in glucose (p=0.019), insulin (p=0.047), HOMA-IR (p=0.022) and triglyceride (p=0.027); absent in BPD and LABG. FGF-21 levels in SG appeared as a significant predictor of HOMA-IR change post-surgery (p<0.05). FGF-19 levels post-surgery increased by 31% in SG compared to 10% rise in BPD and 39% decrease in LAGB with significant differences between SG and LAGB (p=0.012). FGF-19 change in BPD inversely correlated with changes in weight (p=0.012), BMI (p=0.037), waist circumference (p=0.044); absent in SG and LAGB. Inflammatory mark-ers post-surgery were significantly reduced in all surgeries (TLR2: p<0.01, MYD88: p<0.01, TRAF6: p<0.01, IKK: p<0.01 and NFkb: p<0.01).

Conclusion: SG appears to have a beneficial influence on FGF-21 and FGF-19 levels irrespective of reduced AT inflammation.

2107‑PSurvivin, a Key Player in Cancer Progression, Increases in Obesity and Protects Adipose Tissue Stem Cells from ApoptosisSONIA FERNANDEZ-VELEDO, MIRIAM EJARQUE, VICTORIA CEPERUELO-MAL-LAFRÉ, CAROLINA SERENA, GISELA PACHON, FRANCISCO J. TINAHONES, MIGUEL A. PEINADO, JOAN VENDRELL, Tarragona, Spain, Boston, MA, Malaga, Spain, Badalona, Spain

Adipose tissue (AT) has a central role in obesity-related metabolic imbal-ance through the dysregulated production of cytokines and adipokines. In addition to its known risk for cardiovascular disease and diabetes, obesity is also a major risk for cancer. Human adipocyte-derived stem cells (hASCs) are important players in pathological development of obesity and associated cancers; however, the mechanisms underlying hASC-induced alterations in cancer remain unknown. We investigated the impact of obesity for the expression of survivin, an anti-apoptotic protein upregulated by adipokines and a diagnostic biomarker of tumor onset and recurrence. In a cross-sec-tional study of 111 subjects classified by body-mass index, circulating levels of survivin and gene expression in subcutaneous AT were significantly higher in obese patients and positively correlated with leptin. Within AT, survivin was detected in hASCs, and its expression was significantly increased in obesity and by pro-inflammatory soluble factors as IL-1β. Analysis of survivin expression in hASCs revealed a complex regulation including epigenetic modifications and protein stability. Surprisingly, obese hASCs showed sur-vivin promoter hypermethylation that correlated with a significant decrease in its mRNA levels. Nonetheless, a lower level of mir-203, which inhibits protein translation, and higher protein stability was found in obese hASCs. We uncovered that survivin levels determine the susceptibility of hASCs to apoptotic stimuli. Accordingly, hASCs from an obese setting were protected from apoptosis. Collectively, these data shed new light on the molecular mechanisms governing AT expansion in obesity through promotion of hASCs that are resistant to apoptosis, and point to survivin as a new molecular player in the communication between hASCs and tumor cells. Thus, inhibi-tion of apoptosis targeting survivin might represent an effective strategy for both obesity and cancer therapy.

Supported By: Spanish Ministry of Economy and Competitiveness/European Regional Development Fund (JV: PI14/00228, SF-V: BFU2015-70454-REDT, SAF2015-65019R); Spanish Biomedical Research Center in Diabetes and Associ-ated Metabolic Disorders

2108‑PThe Impact of ER Stress on Mitochondrial Inefficiency in Human AdipocytesLAURA JACKISCH, LUCIA MARTINEZ DE LA ESCALERA, ALICE MURPHY, PHILIP G. MCTERNAN, HARPAL RANDEVA, GYANENDRA TRIPATHI, Coventry, United Kingdom, London, United Kingdom

Cellular damage in the ER and mitochondria are known to contribute to the pathology of obesity mediated T2DM. This damage may occur in part

(CART), galanin (GAL), galanin-like peptide (GALP), ghrelin (GHRL), pyroglu-tamylated RFamide peptide (QRFP), agouti-related peptide (AGRP), neuro-peptide Y (NPY) and melanocortin 4 receptor (MC4R) by real-time RT-PCR. IH significantly increased the mRNA levels of POMC and CART in all the neu-ronal cells, while the IH-specific increases were not observed in the other genes. The reporter plasmids containing several lengths of POMC and CART promoter fragments were transfected into NB-1 cells and the cells were exposed to IH or normoxia. Deletion analysis revealed that the -705 to -686 promoter region of POMC and the -950 to -929 region of CART are essential for the IH-induced promoter activity. As these two regions contained GATA-1 binding sequences, we introduced small interfering (si) RNA against human GATA-1 mRNA into NB-1 cells and the cells were exposed to IH or normoxia. Real-time RT-PCR revealed that the introduction of GATA-1 siRNA abolished the IH-induced up-regulation of POMC and CART mRNAs. These results indi-cate that IH- stress up-regulates the mRNA levels of anorexigenic peptides, POMC and CART, in human neuronal cells via GATA-1 binding to the promot-ers and suggest that obesity, frequently observed in SAS patients, is not induced by the changes in IH-induced neuropeptide expression.

2105‑PThe Comparison of Body Composition in Metformin Inadequately Controlled Type 2 Diabetes Patients following Exenatide vs. Insulin GlargineWENHUAN FENG, TINGTING YIN, YAN BI, PING LI, SHANMEI SHEN, WEIMIN WANG, CAN JIANG, JUNXIAN TAO, YAN WANG, DALONG ZHU, Nanjing, China

To compare body composition in metformin inadequately glycemic con-trolled T2DM patients following exenatide vs. glargine. This prospective, randomized study enrolled 37 T2DM patients assigned to exenatide or glargine for 16 weeks intervention. Dual-Energy X-ray Absorptiometry was used to assess body composition. After interventions, weight, BMI, waist-line, kilograms and percentages of fat mass in total, trunk, limbs, android and gynoid were lower with exenatide (p<0.05), while weight and BMI increased by glargine (p<0.05). Percentages of lean tissue in above body parts were increased with exenatide (p<0.05), but not changed by glargine. Reductions in weight, BMI, waistline, kilograms and percentages of fat mass in above body parts were greater by exenatide than by glargine (p<0.05) (Figure 1). Except for limbs, more fat mass than lean tissue reduced with exenatide (p<0.05). Similar reduction of FBG, HbA1c and similar increase of insulin resistance and insulin sensitivity index in the two groups (p<0.05). For met-formin inadequately controlled T2DM patients, the same improvement of glycemic control, insulin sensitivity and β-cell function were achieved by combining exenatide or glargine, while more weight, BMI, waistline, fat mass reduced by exenatide and weight loss with exenatide mainly came from fat mass reduction.

Figure 1.

Supported By: National Natural Science Foundation of China (81570736, 81570737); Medical and Health Research Projects of Nanjing Health Bureau in Jiangsu Province of China (YKK14055); Project of Standardized Diagnosis and Treatment of Key Diseases in Jiangsu Province of China (2015604)

2106‑PEffects of Bariatric Surgery on FGF‑19 and FGF‑21 Levels in Obese Diabetic WomenSAHAR AZHARIAN, ALICE MURPHY, LUCIA MARTINEZ DE LA ESCALERA, IOAN-NIS KYROU, JANA VRBIKOVA, VOITECH HAINER, PETRA SRAMKOVA, MAR-TIN FRIED, SUDHESH KUMAR, GYANENDRA TRIPATHI, PHILIP G. MCTERNAN, MILAN K. PIYA, Coventry, United Kingdom, Birmingham, United Kingdom, Prague, Czech Republic, London, United Kingdom

Background: Fibroblast growth factor-19 (FGF-19) and FGF-21 regulate glucose tolerance and insulin sensitivity, which in type 2 diabetes mel-

A554


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

of behaviour changes during, the implant period. The first 12 patients (age 52.4 ± 9.3 yr, 33.3% male, diabetes duration 17 (10-25) yr, 75% on insulin, BMI 41.7 ± 9.8 kg/m2) have completed 6 months post Endobarrier removal. During 1 yr’s implant, mean ± SD HbA1c fell by 2.4 ± 1.9%, from 9.6 ± 2.1 to 7.2 ± 1.0% (p=0.001), weight fell by 17.6 ± 8.9 kg from 117.0 ± 28.3 to 99.4 ± 28.8 kg (p= 0.000) and systolic BP from 143.8 ± 12.5 to 129.7 ± 15.2 mmHg (p=0.011). Median (IQR) total daily insulin dose reduced from 104 (51-120) to 48 (0-68) units (p=0.024), n=9. 6 months post-explant (Figure) insulin dose continued to fall. The rises in mean HbA1c, weight and BMI were not statistically significant and all remained considerably lower than baseline. 9 (75%) patients sustained their significant metabolic improvement achieved with Endobarrier throughout the 18 months. They reported considerable improvements in well-being, energy, fitness, exercise ability; 4/9 (44%) insulin-treated patients discontinued insulin. They believed that they had forever changed their poor eating habits and felt Endobarrier had helped in achieving this. Of the 3 patients whose weight/glycaemic control worsened, all had depression.

2111‑PInteraction between Islet Cell Antibody Positivity and Efficacy of the Look AHEAD Lifestyle InterventionSCOTT J. PILLA, ASHOK BALASUBRAMANYAM, WILLIAM C. KNOWLER, MARI-ANA LAZO, DAVID M. NATHAN, XAVIER PI-SUNYER, JEANNE M. CLARK, NISA M. MARUTHUR, Baltimore, MD, Houston, TX, Phoenix, AZ, Boston, MA, New York, NY

Antibodies to pancreatic islet cells are detected in a subset of patients diagnosed with type 2 diabetes and are associated with lower adiposity and pancreatic β-cell function. The UKPDS 25 study suggested that a lifestyle intervention may not be as beneficial for these patients. To determine the impact of islet cell antibody positivity on the efficacy of diabetes lifestyle interventions, glutamic acid decarboxylase antibodies (GADA) were mea-sured in stored serum from 198 participants at 1 site of the Look AHEAD (Action for Health in Diabetes) trial. Look AHEAD randomized overweight/obese patients with type 2 diabetes to an Intensive Lifestyle Intervention (ILI) aimed at achieving weight loss, or the control group, Diabetes Support and Education (DSE). The Wilcoxon rank-sum test was used to compare baseline characteristics by GADA positivity. T-tests were used to compare the % weight change from baseline in the ILI and DSE arms, averaged over 4 years of follow-up. GADA positivity (11 of 198 patients, 5.6%) was associ-ated with a higher HDL (54.2 vs. 44.2 mg/dl, P = 0.025) and a trend towards lower fasting C-peptide (1.19 vs. 1.97 mg/dl, P = 0.058). There was no differ-ence in baseline weight or BMI by antibody status. The weight loss efficacy of the intervention differed significantly by antibody status (P interaction = 0.024). Averaged across four years, GADA(-) patients lost more weight in the ILI arm (n = 94) than in the DSE arm (n = 91) (-5.23% vs. +0.87% weight change, P < 0.001). GADA(+) patients lost weight in both arms, but less in the ILI arm (n = 6) than in the DSE arm (n = 5) which was not significant (-3.77% vs. -6.24% weight change, P = 0.53). GADA(-) and GADA(+) patients had the same average HbA1c during follow-up (6.9% vs. 6.9%, P = 0.99). These data suggest that GADA(+) patients with type 2 diabetes may lose weight regard-less of a lifestyle intervention. Future work will measure additional islet cell antibodies and use a larger sample.

as a consequence of ER-mitochondria cross talk in conditions of nutrient excess such as obesity. To date insight into this dynamic relationship is not well characterised in human adipocytes. Therefore this study investigated whether the induction of ER stress contributes to the development of mito-chondrial inefficiency in human adipocytes.

Human differentiated adipocytes from 1) Chub-S7 cell line and 2) primary lean and obese abdominal subcutaneous (AbdSC) adipocytes, were treated with Tunicamycin (Tn) to induce ER stress over time. Key parameters of mito-chondrial function were assessed, including oxygen consumption rate (OCR), mitochondrial membrane potential (MMP), ATP concentration, mitochondrial dynamics and number.

Induction of ER stress led to a 26% (P≤0.001) increase in OCR in Chub-S7 cells in a concentration dependent manner. This increase in OCR also corre-sponded to diminished ATP production (26%↓; P≤0.001) and impaired MMP (32%↓; P≤0.0001), highlighting the formation of inefficient mitochondria due to ER stress. Morphological analysis via confocal microscopy also revealed a reduction mitochondrial elongation (16%↓; P≤0.05) and cellular area occu-pied by mitochondria (28%↓; P≤0.05). Furthermore, AbdSc adipocytes from lean subjects mirrored the Chub-S7 cellular response with a 21% (p≤0.01) rise in OCR by Tn treatment. In contrast, mitochondria from obese subjects displayed 33% (p≤0.001) lower basal respiration than their lean counter-parts and were not responsive to Tn, demonstrating significantly impaired respiratory function.

In summary, these human data suggest that adipocyte mitochondrial inef-ficiency is impacted by ER stress and exacerbated in obesity. Together these findings indicate the important relationship between the ER and mitochon-dria as a mechanism to contribute to obesity mediated T2DM.

Supported By: Warwick Medical School

2109‑PThe Power of Broccoli Superfood: Measuring and Modeling ER Stress in Human AdipocytesALICE MURPHY, SAHAR AZHARIAN, LAURA JACKISCH, LUCIA MARTINEZ DE LA ESCALERA CLAPP, ALANOUD ALADEL, GUY C. BARKER, MICHAEL J. CHAPPELL, PHILIP G. MCTERNAN, Coventry, United Kingdom

Background: Excess dietary nutrients available during obesity can lead to cellular stress by causing the disruption of protein folding in the endoplasmic reticulum (ER). This can result in ER stress, a response that causes inflamma-tion, leading to type 2 diabetes mellitus (T2DM). Thus, investigating whether nutrients such as freeze dried broccoli extract (BE) can reduce this cellular damage in human adipocytes is important. To test this hypothesis a math-ematical model of the ER stress pathway was created. This parameterised model assessed competitive and non-competitive rate limiting steps and the input of time on species (protein molecules, e.g., PERK) change, during a perturbation event.

Methods: Differentiated Chub-S7 cells were treated with 10ng/ml BE (hybrid Brassica oleracea var. italic) alone, or combined with 750ng/ml tunicamycin (Tun), an inducer of ER stress. The three ER stress pathways (PERK, IRE1, ATF6) were measured at 18 time points between 0 hr and 72 hr by qRT-PCR and Western blot. The Hill equation and Michaelis-Menten kinetics were used to create ordinary differential equations (ODEs) to model ER stress over the time series events.

Results: Tun significantly increased ER stress markers up to 4.6 fold in a time dependent manner (P<0.05). BE combined with Tun significantly reduced expression of these markers by up to 64% compared with Tun alone (P<0.05). The ODE model identified time dependent rate limiting steps and species accumulation. Utilising the real-life experimental data allowed a sensitiv-ity analysis of the model parameters and their effect on model responses, reducing the simulation outcomes to data error by an average of 89%, yield-ing good overall qualitative agreement with the experimental findings.

Conclusion: These studies highlight that the parameterised, validated model has the potential to be useful in predicting cellular ER stress response. Furthermore, our studies suggest a mechanism by which broccoli extract alone may reduce T2DM risk in human adipocytes.

Supported By: Engineering and Physical Sciences Research Council

2110‑PMaintenance of Efficacy after Endobarrier in UK First National Health Service (NHS) Endobarrier ServiceROBERT E.J. RYDER, MAHENDER YADAGIRI, JOHN P. BLEASDALE, EDWARD N. FOGDEN, MARK R. ANDERSON, PIYA SEN GUPTA, Birmingham, United Kingdom

Endobarrier, a 60 cm endoscopically implanted proximal intestinal liner, reduces weight and HbA1c over 1 yr. In the 1st NHS Endobarrier service we primed patients to maintain improvements after, by suggesting institution

A555


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

2114‑PEpicardial Fat Expresses Glucagon‑Like Peptide‑1 Receptor: A New Pharmaceutical Target in Diabetes and Cardiometabolic DiseasesGIANLUCA IACOBELLIS, VLADIMIR CAMARENA, DAVID SANT, GAOFENG WANG, Miami, FL

Epicardial adipose tissue (EAT) is the visceral fat of the heart displaying unique anatomy, functionality and pro-inflammatory transcriptome. EAT can locally affect the myocardium and coronary arteries. EAT is easily measur-able with ultrasound and serves as therapeutic target for pharmaceutical agents targeting the fat. Glucagon-like peptide-1 analogues (GLP-1A) are newer drugs showing beneficial cardiovascular and metabolic effects. Lira-glutide, a GLP-1A, has shown to reduce the risk of cardiovascular events and substantially shrink EAT in subjects with type 2 diabetes and obesity. Whether the beneficial cardiovascular effects of GLP-1A could be attributed to a direct drug-effect on EAT is unclear.

Aim: The presence of GLP-1 receptor (GLP-1R) in EAT would support the hypothesis of a direct effect of GLP-1A on the adipose tissue of the heart, but whether EAT expresses GLP-1R is unknown and unexplored.

Methods: RNA-seq analysis and Quantitative real-time RT-PCR (qRT-PCR) were performed to evaluate the presence of GLP-1R in EAT obtained from 8 subjects with coronary artery disease and type 2 diabetes undergoing elec-tive cardiac surgery.

Results: RNA-sequencing (RNA-seq) analysis showed that EAT expresses GLP-1R gene. qRT-PCR analysis confirmed that GLP-1R expression was detected by two different sets of intron-spanning primers. GLP-1R expres-sion was detected in all patients. The combination of accurately-spliced reads from RNA-seq and successful amplification using intron-spanning primers indicates that expression of GLP-1R is present in EAT.

Conclusions: This is the first time that human EAT is found to express GLP-1R gene and mRNA. GLP-1 activation can target and improve EAT insulin sen-sitivity and thermogenesis, and therefore protect the adjacent myocardium. Our finding suggests that pharmacologically targeting EAT, a measurable and modifiable visceral fat depot, may produce beneficial cardiovascular and metabolic effects.

2115‑PDeveloping a Prediction Model to Clarify the Relationship between the BMI and the Risk for Nonalcoholic Fatty Liver Disease Based on a Modeling and Simulation ApproachKENTARO ONIKI, YUKI SAKAMOTO, MIKU KUDO, TATSUMASA ONO, KAZUKI MATSUDA, NARUMI MUTO, TOMOKO IZUKA, TAKEHISA WATANABE, KOJI OTAKE, YASUHIRO OGATA, JUNJI SARUWATARI, Kumamoto, Japan

Recent evidence has shown that obesity is closely related to the risk of nonalcoholic fatty liver disease (NAFLD), which is an independent risk factor for type 2 diabetes and its complications. However, NAFLD is also found in normal-weight individuals, especially in Asian populations. The goal of this study was to develop a prediction model of NAFLD based on the body mass index (BMI) as the exposure variable using a modeling and simula-tion approach among 394 Japanese health screening program participants (237 males and 156 females, age: 67.5 ± 6.0 years). A nonlinear mixed-effect model best represented the sigmoidal relationship of BMI with the logit function for the probability (Pr) of NAFLD prevalence. A female gender, low value of high-density lipoprotein cholesterol (HDL-C) and high value of low-density lipoprotein cholesterol (LDL-C) increased the risk for NAFLD regard-less of BMI. Meanwhile, a high HbA1c value and patatin-like phospholipase 3 rs738409 G allele carriers reduced the half maximal BMI value (BMI50) for the development of NAFLD. The prediction model for the risk of NAFLD was as follows: Logit(Pr) = -5 + {Logit(Pr)max × (BMI - 17)3.43}/{(BMI50 - 17)3.43 + (BMI - 17)3.43} Logit(Pr)max = 4.17 + 1.02female - 0.060 × (HDL-C - 69.4) + 0.009 × (LDL-C - 120) BMI50 =17 + 6.42 × 0.760PNPLA3 C/G genotype × 0.591PNPLA3 G/G genotype × (HbA1c/5.88)-3.34. Determining the patients at high-risk for developing NAFLD using the present prediction model may thus help prevent NAFLD and its complications by facilitating targeted prevention and treatment pro-grams for high-risk groups.

Supported By: Japan Society for the Promotion of Science; Japan Research Foundation for Clinical Pharmacology

2116‑PGastric Bypass Surgery Is Associated with a Reduction in Vasocon‑strictive MediatorsPARESH DANDONA, HUSAM GHANIM, SCOTT V. MONTE, JOSEPH CARUANA, MAYURI MUDGAL, SANAA ABUAYSHEH, Buffalo, NY

Obesity is known to be associated with hypertension. Since gastric bypass surgery is associated with a reduction in blood pressure, we hypoth-

2112‑PImpact on Adipokines and Inflammation of Short‑Term Weight Loss by Bariatric Surgery vs. Very Low Calorie DietAMALIA GASTALDELLI, MARIA CHIARA MAGNONE, MELANIA GAGGINI, AMERIGO IACONELLI, AUGUSTO VENEZIANI, FRANCESCO RUBINO, GELTRUDE MINGRONE, Pisa, Italy, Basel, Switzerland, Rome, Italy, London, United Kingdom

Bariatric surgery has been shown to have important long term metabolic effects. We have recently shown that metabolic improvements are evident already 1-week after surgery.

The aim of the present study was to evaluate if short term weight loss obtained with bariatric surgical procedures vs. very low caloric intake (VLCI) was sufficient to change plasma levels of adipokines and inflammatory markers.

We studied 20 obese nondiabetic patients (BMI=44.2±0.7 kg/m2). At baseline and 1-week after VLCI (600 kcal/day) subjects received a euglyce-mic insulin clamp (IC) with tracer infusion to quantify endogenous glucose production (EGP), lipolysis (RaGlycerol), peripheral (M/I), hepatic (Hep-IS=1/(EGP·Ins)) and adipose (Adipo-IS=1/(RaGlycerol·Ins)) insulin sensitivity (IS). Approximately 3-months later patients were admitted for gastric banding LAGB (n=10) or bypass RYGB (n=10), and re-studied with IC 1-week after surgery under the same caloric regime. At each step we measured fasting concentrations of adiponectin, leptin, resistin, ICAM, VCAM, E-selectin, PP, C-Reactive Protein (CRP).

After 1-week of VLCI, patients lost 2.1kg without significant changes in Hep-IS, Adipo-IS, M/I or DI. RYGB and LAGB led to greater weight loss, (5.5 and 5.2kg) and significant improvement in Hep-IS, EGP and lipolysis. Only RYGB improved Adipo-IS and M/I. M/I was associated positively with adipo-nectin (r=0.27) and negatively with E-selectin (r=-0.33) and VCAM (r=-0.26), (p<0.03). Inflammatory markers were not changed significantly after VLCI. After surgery E-selectin and ICAM were reduced only after RYGB, leptin also after LAGB, while no significant change was observed in adiponectin, CRP, VCAM, PP, Resistin probably because of the short time of the observation.

Conclusions: Bariatric surgery improves insulin sensitivity within 1-week. The metabolic effects and the improvement in inflammatory markers were independent of caloric intake and more pronounced after RYGB vs. LAGB.

Supported By: F. Hoffmann-La Roche Ltd.

2113‑PAssociations of Serum Fibroblast Growth Factor‑23 Levels with Obesity and Abdominal Fat DistributionXIANG HU, XIAOJING MA, YUQI LUO, YITING XU, QIN XIONG, XIAOPING PAN, YUNFENG XIAO, YUQIAN BAO, WEIPING JIA, Shanghai, China

Background and Aim: Fibroblast growth factor-23 (FGF-23) is generally acknowledged as a central regulator in mineral homeostasis. Recent findings raise the possibility that FGF-23 may be related to the body fat content and abdominal fat distribution. The present study aimed to elucidate the associa-tions of serum FGF-23 levels with obesity and visceral fat accumulation.

Methods: A total of 1,599 normoglycemic subjects with preserved kidney function, including 597 men, 411 premenopausal women, and 591 postmeno-pausal women, were enrolled. Intact FGF-23 were detected in serum sample using a sandwich enzyme-linked immunosorbent assay. Overweight/obesity was defined by a body mass index of ≥ 25.0 kg/m2. Visceral fat area (VFA) was assessed by magnetic resonance imaging and used to define abdominal obesity with the value of ≥ 80 cm2.

Results: No matter with or without overweight/obesity, men with abdomi-nal obesity exhibited higher serum FGF-23 levels (both P < 0.05). In premeno-pausal women, serum FGF-23 levels were not higher in those with over-weight/obesity and/or abdominal obesity (all P > 0.05). In postmenopausal women, serum FGF-23 levels were elevated in subjects with overweight/obe-sity and/or abdominal obesity (all P < 0.05). Each one-unit increase in VFA was associated with a 0.028-pg/mL and a 0.051-pg/mL increase in serum FGF-23 levels in men (P = 0.001) and postmenopausal women (P < 0.001), respec-tively. Whether concomitant with overweight/obesity or not, the presence of abdominal obesity was independently associated with the increase in serum FGF-23 levels in men and postmenopausal women (all P < 0.05).

Conclusion: Serum FGF-23 levels are elevated in obese population, especially individuals with abdominal obesity. The independent and posi-tive associations between the presence of abdominal obesity and serum FGF2-3 levels in specific gender groups suggest that serum FGF-23 levels may indicate the risk of metabolic and cardiovascular disease in men and postmenopausal women.

Supported By: National Basic Research Program of China; Shanghai Health and Family Planning Commission; Shanghai Jiao Tong University

A556


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

annual examinations during the follow-up to exclude chance proteinuria as much as possible.

Results: During the 81,660 person-years follow-up period, we confirmed 390 cases of consecutive proteinuria. After adjusted for known risk factors, compared with metabolically healthy normal weight, metabolically healthy obesity was not associated with the risk of consecutive proteinuria (hazard ratio 0.86 (95% CI 0.37-1.99). Multiple-adjusted hazard ratios of metabolically unhealthy normal weight (metabolic components =1), metabolically unhealthy normal weight (metabolic components ≥2), metabolically unhealthy obesity (metabolic components =1), and metabolically unhealthy obesity (metabolic components ≥2) were 1.17 (95% CI 0.85-1.62), 1.77 (95% CI 1.30-2.42), 1.71 (95% CI 1.12-2.61), and 2.77 (95% CI 2.01-3.82), respectively.

Conclusion: Metabolically healthy obesity did not increase the risk of pro-teinuria in middle-aged Japanese men.


2119‑PEffect on Body Weight of Naltrexone/Bupropion in Overweight and Obese Participants with Type 2 Diabetes and Cardiovascular Risk Factors in a Large, Randomized, Double‑Blind StudySTEVEN R. SMITH, JOHN B. BUSE, KYE GILDER, KEVIN SHAN, AMY HALSETH, Winter Park, FL, Chapel Hill, NC, La Jolla, CA

Extended-release naltrexone 32 mg/bupropion 360 mg (NB) is indicated as an adjunct to diet and physical activity for chronic weight management. This study assessed the effect of NB on major adverse cardiovascular events (MACE) in overweight and obese participants at elevated cardiovas-cular (CV) risk. Randomized participants (NB or placebo [PBO]) received an internet-based weight management program and were required to lose ≥2% body weight at 16 wks, without a sustained increase in blood pressure, to continue study medication.

This study was terminated early after the second interim analysis (IA2), with 50% of MACE data collected. Data on CV endpoints in intent-to-treat (ITT) population were previously published. The current analyses focus on change in body weight in the population with type 2 diabetes (T2DM), 85.2% of ITT.

The T2DM population (PBO N=3803, NB N=3784) was 56.7% female, 82.1% white, mean age 60.7 yrs, BMI 37.4 kg/m2, 20.4% had CV disease, 23.3% baseline insulin use, HbA1c 7.4%, and a median duration of T2DM of 7.8 yrs.

In participants with T2DM who completed the 52 wk visit, analysis showed greater mean percent change in body weight (M%DBW) with NB (-4.4% (SD 6.7%)) vs. PBO (-1.7% (SD 5.3%)). Participants achieving ≥5% reduction in weight was 40.4% on NB vs. 21.4% on PBO. In an on-treatment analysis, in which weight data collected >30 days after last dose was excluded, both groups demonstrated greater weight loss (NB [-7.3% (SD 6.1%); n=1417], PBO [-3.9% (5.3%); n=989]. At 104 wks, on-treatment M%DBW was -7.0% with NB (SD 7.0%; n=997) vs. -4.2% with PBO (SD 7.3%; n=638). Serious adverse events (AE) and AEs leading to discontinuation of study medication were similar between those with and without T2DM, and gastrointestinal disor-ders were the most common AEs leading to discontinuation of NB.

In this older population with T2DM and elevated CV risk, weight loss was similar to participants with T2DM in Phase 3 study.

2120‑PVisceral Fat Estimation by Dual‑Bioelectrical Impedance Analysis Is Useful to Predict Cardiovascular Risk Factors In Type 2 DiabetesYOKO OHATA, CHEOL SON, RYO KOEZUKA, HISASHI MAKINO, MAYU TOCHIYA, TAMIKO TAMANAHA, MASAHIRO HIGASHI, ICHIRO KISHIMOTO, KIMINORI HOSODA, Suita, Japan

Background: Visceral adiposity is thought to be a good surrogate marker of obesity-related defects. Visceral fat area (VFA) calculated by an X-ray computed tomography (CT) has been used as one of major indices for obesity-related diseases; however, this method is expensive and needs exposure to radiation. Dual-bioelectrical impedance analysis (BIA) is a new, simple, noninvasive and cost effective method for the measurement of VFA. It remains unknown whether VFA measured by BIA is useful in the diabetic patients that often have complications potentially affecting the impedance analysis such as nephropathy and cardiovascular diseases.

Objectives: This study aimed to examine the usefulness of VFA measure-ment by BIA to predict cardiovascular risk factors in patients with type 2 diabetes.

Design and Methods: In 98 patients, correlations between the VFAs esti-mated by dual-BIA and by CT, anthropometric parameters, blood test results and the number of risk factors (hypertension and dyslipidemia) were assessed.

esized that weight loss following surgery in morbidly obese patients is asso-ciated with a decrease in plasma concentrations of vasoconstrictors and an increase in the concentrations of vasodilators. Fourteen patients with morbid obesity and diabetes were investigated at baseline and 6 months after Roux-en-Y gastric bypass (RYGB) surgery. Fasting blood samples were collected and plasma and serum s separated for the measurement of vasoconstrictors, angiotensinogen, renin and angiotensin II; and vasodila-tors, ANP, BNP, cGMP, and cAMP. The expression of angiotensin converting enzyme (ACE) in circulating MNC was also measured. Six months following RYGB, BMI fell from 51.3±12.0 to 41.6±10.4 kg/m2 and there were significant improvements in the HbA1C. Systolic but not diastolic blood pressure fell significantly at 6 months (from 135±13 to 124±±11 mmHg; p< 0.05). Plasma concentrations of angiotensinogen, angiotensin II and renin fell significantly at 6 months by 22±10% 22±8% and 35±13%, 9p<0.05 for all) respectively, at 6 month following surgery. Plasma concentrations of ANP concentrations increased significantly by 24±13% at 6 months while there was no significant change in BNP, cAMP or cGMP concentrations. ACE mRNA expression did not alter. It is thus likely that the hypertension of obesity is associated with an activation of RAS which diminishes with weight loss. Simultaneous with an increase in ANP suggests that this vasodilator may contribute to the fall in blood pressure following RYGB.

2117‑PBeta‑Cell Function Decline in Mexican Americans: Role of Weight Gain and AdipokinesANNY H. XIANG, MARY HELEN BLACK, YU-HSIANG SHU, JUN WU, ADRI-ENNE MACKAY, CORINNA KOEBNICK, RICHARD M. WATANABE, THOMAS A. BUCHANAN, Pasadena, CA, Aliso Viejo, CA, Los Angeles, CA

Obesity contributes to β-cell dysfunction that causes type 2 diabetes (T2D). The present study examines the potential role of weight gain and adi-pokines in mediating this effect. 361 Mexican Americans without T2D from The BetaGene longitudinal study had BMI, body fat, 16 circulating biomark-ers, OGTT and frequently sampled IV glucose tolerance (FSIGT) testing at baseline (age 34.6 ± 8.2 years, 73% female) and after a median of 4.2 years follow-up. Insulin sensitivity (SI) and β-cell function (disposition index, DI) were estimated from the FSIGTs. The 16 biomarkers were adiponectin, IL-18, IL-1β, IL-6, IL-1Ra, leptin, lipocalin, MCP-1, resistin, TNF-α, apelin, C-reactive protein (CRP), DPP-4, visfatin, SFRP4 and SFRP5. Regression models were used with adjustment for age and sex. Six factors were each significantly associated with rate of change in DI: baseline adiponectin and DPP-4 (both direct associations); rates of change in weight or body fat, CRP, IL-6 and leptin (all inverse associations). In multivariate analysis, baseline adiponec-tin (p=0.002) and DPP-4 (p=0.03), and changes in weight (p<0.0001) and IL-6 (p=0.012) were independently associated with rate of change in DI. Adjust-ment for changes in CRP and leptin reduced by 20% the association between change in weight and change in DI, but the association remained significant (p=0.019). Adjustment of change in CRP and leptin had little effect on the DI association with the other three factors. Adjustment for change in SI eliminated the DI association with weight change (p=0.79) and IL-6 (p=0.27), weakened the association between DI and baseline DPP-4 (p=0.09) and had little effect on the association with baseline adiponectin (p=0.009). Thus, in Mexican Americans, decline in β-cell function was associated with weight gain, which was partially explained by increase in CRP and leptin. Circulating adiponectin may help to protect against declining β-cell function indepen-dent of weight gain and change in insulin resistance and other adipokines.

Supported By: National Institutes of Health (DK100302-01A1)

2118‑PThe Association between Metabolically Healthy Obese Phenotype and the Risk of Proteinuria: The Kansai Health Care StudySHINICHIRO UEHARA, KYOKO K. SATO, MIKIKO SHIBATA, KEIKO OUE, HIROSHI KAMBE, MICHIO MORIMOTO, TOMOSHIGE HAYASHI, Osaka, Japan

Background: Metabolically healthy obesity seems to be unique phenotype for the risk of cardiometabolic diseases. However, it is not known whether this phenotype is associated with the risk of proteinuria.

Methods: Study subjects were 9,185 nondiabetic Japanese men aged 40-55 years who had no proteinuria, an estimated glomerular filtration rate ≥60 mL/min/1.73 m2, no history of cancer, and no use of antihypertensive and oral lipid-lowering medications at baseline. Obesity was defended as body mass index ≥25.0 kg/m2. Metabolic health was defined as no compo-nents of the metabolic syndrome criteria excluding waist circumference by Adult Treatment Panel III and metabolic unhealth as one or more compo-nents. The incidence of proteinuria was defined as “consecutive proteinuria” if it was detected twice consecutively as 1+ or higher on urine dipstick at

A557


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

-0.62 (0.08)% vs. PBO: 0.07 (0.10)% (p<0.001). In those who lost weight at wk 56, NB was associated with greater mean reduction in HbA1c before using rescue medication, for any given amount of weight loss. A mediation analysis showed an indirect contribution of weight loss on HbA1c reduction besides NB treatment. Specifically, 53% of the HbA1c reduction seen with NB relative to PBO was mediated by weight loss. Safety profile from this study was similar to those without T2DM and was previously published.

NB, when combined with lifestyle modification, resulted in significant gly-cemic improvement and weight loss, with over half of the HbA1c reduction mediated by weight loss.

2123‑PEarly Achievement of Significant Weight Loss with Naltrexone/Bupropion Is Associated with Additional Weight Loss and Improved Glycemic Control at One Year in Patients with Type 2 DiabetesRAY PLODKOWSKI, PRISCILLA A. HOLLANDER, LISETTE ACEVADO, KYE GILDER, AMY HALSETH, La Jolla, CA, Dallas, TX

Extended-release naltrexone 32 mg/bupropion 360 mg (NB) is approved for chronic weight management as an adjunct to diet and physical activity. A phase 3 study in patients with type 2 diabetes (T2DM) demonstrated sig-nificantly greater weight loss with NB vs. placebo (PBO). As early response to treatment predicts long-term weight loss, the current analysis was per-formed to evaluate weight loss and glycemic effects in early responders, which is defined as patients who achieve ≥5% weight loss at wk 16.

Efficacy analyses were performed on the full analysis set (FAS), defined as randomized patients with at least one post-baseline (BL) weight mea-surement while on study medication. BL characteristics in the FAS (N=265 NB, N=159 PBO) were similar between treatment groups: 54% female, with mean BL age 54 yrs, BMI 36.6 kg/m2, HbA1c of 8.0%, and FPG of 161 mg/dL. Weight loss of ≥5% at wk 16 was achieved in 41% of NB patients and 13% of PBO patients. 88% of NB early responders (NB-Responders) completed 56 wks of treatment. In NB-Responders, mean (SE) weight loss at wk 16 was 8.5 (0.2)%, and at wk 56 it was reduced by 9.1 (0.5)% from BL. At wk 56 NB-Responders exhibited a least squares (LS) mean (SE) change of -1.01 (0.09)% in HbA1c vs. PBO 0.14 (0.09)%; FPG decreased 19.5 (3.6) mg/dL in NB-Responders vs. 4.0 (3.4) mg/dL in PBO. Change in HDL in NB-Responders was 5.4 (0.8) mg/dL vs. -0.3 (0.6) mg/dL in PBO. The most common reason for the discontinuation of study medication was adverse events (NB 29% vs. PBO 15%). The safety profile was similar to that of Phase 3 study participants without T2DM and has been previously published.

Patients treated with NB that achieved ≥5% weight loss by wk 16 exhib-ited additional weight loss and improved glycemic parameters at 1 year, and the majority continued treatment to study end, supporting the use of the wk 16 criteria to predict longer term outcomes in patients with T2DM.

2124‑PComparison of Apolipoprotein (ApoB/ApoA‑1) and Lipoprotein (Total Cholesterol/HDL) Ratios in Obese AdolescentsRAMIN ALEMZADEH, JESSICA C. KICHLER, Memphis, TN, Cincinnati, OH

Background: Serum apoB/apoA-1) ratio is considered a stronger predictor of systemic inflammation and atherosclerosis than serum total cholesterol/HDL (TC/HDL) ratio among adults. We evaluated the relationships between apoB/apoA-1 and TC/HDL ratios with surrogate markers of inflammation and insulin resistance (IR) among obese adolescents.

Methods: Body mass index z-score (BMI-z), body composition, fasting glucose, insulin, lipids, high sensitive c-reactive protein (hs-CRP), hemo-globin A1c (HbA1c) and homeostatic model assessment for insulin resistance (HOMA-IR), were evaluated in 143 obese adolescents.

Results: Male participants had higher BMI-z, fat-free mass (FFM), and glu-cose than female participants (p<0.01). Further, 54.5% of participants met diagnostic criteria for metabolic syndrome (MS) and displayed higher SBP, BMI-z, fat mass (FM), HOMA-IR, hs-CRP, TG, TC/HDL, TG/HDL, apoB/apoA-1 and HbA1c, but lower HDL and apoA-1 than the non-MS group (p<0.05) with similar gender distribution (M: 48.3% vs. F: 56.6%, p=0.31). In the entire cohort, TC/HDL and apoB/apoA-1 ratios were strongly correlated (r=0.81, p<0.0001). ApoB/apoA-1 and TC/HDL-C ratios were positively correlated with SBP (r=0.29; p=0.0004) and (r=0.43; p<0.0001), respectively. Finally, apoB/apoA-1 and TC/HDL-C ratios were correlated with hs-CRP (r=0.21; p=0.014) and (r=0.26; p=0.0016), respectively. However, the relationships between apoB/apoA-1 and TC/HDL ratios with HOMA-IR were not statisti-cally significant.

Conclusions: Unlike in the adult population, serum apoA-1, apoB and apoB/apoA-1 ratio may not have significant advantage over conventional lipopro-teins in evaluating the presence of systemic inflammation and risk of ath-

Results: We found that the measurement error between the VFAs estimated by the two methods were greater among the patients with BNP≧100pg/dl than those with BNP<100pg/dl. VFA by dual-BIA correlated significantly with VFA by CT (r = 0.917, p < 0.0001), with a mean error of 18.1 ± 15.8 cm2 among the patients with BNP<100pg/dl that were not thought to have potential fluid retention. The area under the curve (AUC) in receiver operating characteristic (ROC) analysis for VFA by dual-BIA to detect the presence of multiple cardiovascular risk factors was equivalent to that for VFA by CT (p = 0.35).

Conclusions: In type 2 diabetes without potential fluid retention, estimat-ing visceral fat accumulation by dual-BIA is well correlated to that by CT and predicts the cluster of obesity-related cardiovascular risks.

2121‑PEffect of Naltrexone/Bupropion on Cardiovascular Events in Over‑weight and Obese Participants with Type 2 Diabetes and Cardio‑vascular Risk Factors in a Large, Randomized, Double‑Blind StudyJOHN B. BUSE, STEVEN R. SMITH, KYE GILDER, KEVIN SHAN, AMY HALSETH, Chapel Hill, NC, Winter Park, FL, La Jolla, CA

Extended-release naltrexone 32 mg/bupropion 360 mg (NB) is indicated as an adjunct to diet and physical activity for chronic weight management. This study assessed the effect of NB on major adverse cardiovascular events (MACE) in overweight and obese participants at elevated cardiovas-cular (CV) risk. Randomized participants (NB or placebo [PBO]) received an internet-based weight management program and were required to lose ≥2% body weight at 16 wks, without a sustained increase in blood pressure, to continue study medication.

This study was terminated early after the second interim analysis (IA2), with 50% of MACE data collected. Data on CV endpoints in the intent-to-treat (ITT) population were previously published. The current analyses focus on CV endpoints in the population with type 2 diabetes (T2DM), 85.2% of the ITT.

The T2DM population (PBO N=3803, NB N=3784) was 56.7% female, 82.1% white, mean age 60.7 yrs, BMI 37.4 kg/m2, 20.4% had CV disease, HbA1c 7.4%, and a median duration of T2DM of 7.8 yrs.

At IA2, MACE occurred in 77 PBO (2.0%) and 67 NB (1.8%) participants (hazard ratio [HR], 0.87; 99.7% CI, 0.53-1.42). The MACE subcomponents of CV death, nonfatal stroke, and nonfatal myocardial infarction resulted in HR of 0.54, 1.06, and 1.00, respectively, with wider confidence intervals. Results in the T2DM population are consistent with the ITT population. In an ‘on treatment’ analysis, which excluded events occurring >30 days after last dose of study medication, MACE occurred in 27 PBO (0.7%) and 31 NB (0.8%) participants (HR, 0.96; 99.7% CI, 0.44-2.09). Serious adverse events (AE) and AEs leading to discontinuation of study medication were similar between those with and without T2DM, and gastrointestinal disorders were the most common AEs leading to discontinuation of NB.

In this older population with T2DM and elevated CV risk, NB did not dem-onstrate any evidence for increased CV risk compared to PBO.

2122‑PWeight Loss Mediates the Treatment Effect of Naltrexone/Bupro‑pion on Glycemic Control in Patients with Type 2 DiabetesPRISCILLA A. HOLLANDER, RAY PLODKOWSKI, KEVIN SHAN, KYE GILDER, AMY HALSETH, Dallas, TX, La Jolla, CA

Extended-release naltrexone 32 mg/bupropion 360 mg (NB) is approved for chronic weight management as an adjunct to diet and physical activ-ity. Phase 3 studies demonstrated significantly greater weight loss with NB vs. placebo (PBO) with lifestyle modification counseling. A phase 3 study in patients with type 2 diabetes (T2DM) showed a greater reduction in HbA1c with NB vs. PBO.

The current analyses examined the effect of NB on both body weight and HbA1c, and quantified the relative contribution of weight loss to glycemic improvement via a mediation analysis. Analyses were performed on the full analysis set (FAS), defined as randomized patients with at least one post-baseline (BL) body weight measurement while on study medication. Data after the use of glycemic rescue medications were excluded. Safety analy-ses used all randomized patients.

The FAS (NB N=265, PBO N=159) was 54% female, 80% white, with mean BL age of 54 yrs, BMI of 36.6 kg/m2, and HbA1c of 8.0%. The most com-monly reported diabetes medications at BL were metformin (79%) and sul-fonylureas (49%). The most common reason for NB withdrawal was adverse events (29%). Rate of rescue medication was NB: 22% vs. PBO: 35%. At wk 56, least squares (LS) mean (SE) weight percent change was NB: -4.7 (0.31)% vs. PBO: -1.7 (0.39)% (p<0.001 between treatment); HbA1c change was NB:

A558


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

no association was observed between plasma leptin levels and total sleep time in either group.

In conclusion, leptin is associated with sleep quality, independently of BMI, in patients with type 2 diabetes. This study indicates that leptin plays a beneficial role in the quality of sleep by the mechanism independent of obesity.

2127‑PCardiometabolic and Patient‑Reported Outcomes in Obese T2D Patients Three Years after Randomization to Laparoscopic Adjust‑able Gastric Band (LAGB) vs. Intensive Diabetes and Medical Weight Management (IMWM)DONALD C. SIMONSON, FLORENCIA HALPERIN, KATHLEEN FOSTER, STEPHANIE WOROBEY, ASHLEY VERNON, ALLISON B. GOLDFINE, Boston, MA

Bariatric surgery is effective in promoting weight loss and resolution of T2D, but few prospective randomized trials have directly compared surgery to an intensive diabetes and medical weight management program. We ran-domized 40 obese T2D (22 M/18 F; weight 109 ± 15 kg; BMI 36.5 ± 3.7 kg/m2; age 51 ± 10 yrs; HbA1c 8.2 ± 1.2%) to either LAGB (n = 18) or a 12-week multidisciplinary IMWM program (n = 22) with follow-up for 3 yrs. At 1 yr, weight loss after LAGB was greater than IMWM (-13.5 ± 1.3 vs. -8.4 ± 1.2 kg, respectively, p < 0.01), and this difference continued through 3 yrs (-12.0 ± 2.0 vs. -4.8 ± 2.0 kg, p < 0.01). Reductions in HbA1c were initially similar in the two groups (-1.2 ± 0.3 vs. -1.0 ± 0.3% at 1 yr), but LAGB produced a sustained reduction at 3 yrs (-0.8 ± 0.4%, p < 0.05 vs. baseline) vs. IMWM (+0.2 ± 0.4%, p = NS). HDL cholesterol increased more at all times after surgical vs. medical therapy (+10.0 ± 1.7 vs. +2.6 ± 2.7 mg/dl at 3 yrs, p < 0.01), while triglycerides improved similarly in both groups (-33 ± 16 vs. -20 ± 15 mg/dl). Changes in LDL cholesterol, systolic and diastolic BP did not differ between treatments. Self-reported health status (SF-36 physical, mental, and total scores) changed minimally and comparably from baseline with both thera-pies. The Impact of Weight on Quality of Life (IWQoL) and Problem Areas in Diabetes (PAID) improved significantly after both interventions (both p < 0.01), but did not differ between groups. These results indicate that LAGB leads to 1) greater sustained weight loss, 2) improved HbA1c, and 3) higher HDL cholesterol compared with an intensive diabetes and medical weight man-agement program. Changes in triglycerides, LDL cholesterol, BP, and generic and disease-specific measures of self-reported health were similar in both groups. These findings may help guide obese patients with type 2 diabetes when exploring options for diabetes and weight management.

Supported By: National Institutes of Health; Johnson & Johnson; Novo Nordisk; Nestlé

2128‑PThe Impact of Visceral Obesity on Glycated Albumin HbA1c Ratio in Type 2 DiabetesSAORI MARUO, KOKA MOTOYAMA, YOSHINORI KAKUTANI, YUKO YAMAZAKI, TOMOAKI MORIOKA, KATSUHITO MORI, SHINYA FUKUMOTO, ATSUSHI SHIOI, TETSUO SHOJI, MASANORI EMOTO, MASAAKI INABA, Osaka, Japan

Serum glycated albumin (GA) is one of the alternative indicators for chronic glycemic control in diabetes. Recent studies have revealed that GA is inversely influenced by body mass index (BMI) in association with chronic inflammation. This would cause a discrepancy between GA and HbA1c. Moreover, it is reported that visceral fat area (VFA) is negatively correlated with GA in the subjects with normal glucose tolerance, which may due to an alteration of albumin turnover by visceral obesity. However, it is not well studied whether VFA is also significant factor for GA and GA/HbA1c in patients with type 2 diabetes. In this study, we investigate the associa-tion between visceral adiposity and GA or GA/HbA1c in type 2 diabetes. Patients with type 2 diabetes who were hospitalized in Osaka City Univer-sity Hospital were enrolled for this study. (Age 61.3 ± 13.7 years (mean ± SD), n=123, 68 men and 55 women). Patients with anemia, hypoalbuminemia, acute inflammatory disease, or advanced stages of kidney disease were excluded from the study. SFA and VFA were measured by the abdominal dual bioelectrical impedance analysis method. Relationship between SFA or VFA, and GA or GA/HbA1c was analyzed. Patient’s BMI was 26.9 ± 5.3 kg/m2, HbA1c was 8.5 ± 1.6%, and GA was 22.2 ± 6.3%. In simple regression analysis, BMI was inversely correlated with GA (r=-0.238, p=0.008) as well as GA/HbA1c (r=-0.374, p<0.001). On the other hand, BMI and HbA1c was not significantly correlated (r=-0.046, p=0.612). While VFA was significantly correlated with GA (r=-0.306, p<0.001) and GA/HbA1c (r=-0.458, p<0.001), VFA and HbA1c was not correlated. Notably, the correlation between VFA and GA was stronger than the correlation between SFA and GA. Multiple regression analysis including SFA and VFA as an independent factor for GA/

erosclerosis in obese adolescents. Further studies are needed, however, to evaluate importance of apoB/apoA-1 ratio in predicting atherosclerosis in adolescents with MS.

2125‑PPerfluoroalkyl Substances and Changes in Body Weight and Meta‑bolic Parameters in Response to Weight‑Loss Diets: The POUNDS LOST TrialGANG LIU, KLODIAN DHANA, GENG ZONG, LIMING LIANG, JEREMY FURTADO, LU QI, JENNIFER ROOD, GEORGE A. BRAY, FRANK M. SACKS, BRENT COULL, PHILIPPE GRANDJEAN, QI SUN, Boston, MA, New Orleans, LA, Baton Rouge, LA, Odense, Denmark

Background: The role of perfluoroalkyl substances (PFASs) in weight regu-lation is largely unknown in humans.

Objectives: To examine the associations of baseline PFASs with changes in body weight and resting metabolic rate (RMR) in a diet-induced weight-loss trial.

Methods: In the 2-year POUNDS LOST trial, baseline plasma PFASs, including PFOA, PFHxS, PFNA, PFDA, and PFOS, were measured among 621 overweight and obese participants aged 30-70 years. Body weight, RMR, and other metabolic parameters were measured at baseline, 6 months, and 2 years.

Results: Participants lost an average of 6.4 kg of body weight during the first 6 months and subsequently regained an average of 2.7 kg body weight over the period of 6-24 months. Baseline PFASs levels were not associ-ated with body weight or RMR at baseline. After multivariate adjustment including baseline body weight, higher baseline PFOS and PFNA levels were significantly associated with a greater weight regain during the period of 6-24 months. Comparing extreme tertiles, the multivariate-adjusted weight regain was 2.87±0.8 vs. 1.25±0.8 kg for PFOS and 3.02±0.8 vs. 1.49±0.8 kg for PFNA (both P trend=0.02). For the other PFASs, significant associations were only observed in women but not in men: the multivariate-adjusted weight regain was 2.92±1.1 vs. 1.36±1.0 kg for PFOA, 3.27±1.1 vs. 1.39±1.0 kg for PFHxS, and 2.73±1.0 vs. 1.43±1.0 kg for PFDA (all P trend<0.05). Signifi-cant interactions with gender were demonstrated for PFOA and PFHxS. The PFASs levels did not predict weight loss in 0-6 months. In addition, higher baseline PFASs, especially PFOS and PFNA, were significantly associated with a greater decline in RMR during the weight loss period and a less increase in RMR during the weight regain period (P trend<0.05).

Conclusion: In this diet-induced weight-loss setting, higher baseline plasma PFASs levels predict more weight regain, but not weight loss among overweight and obese individuals, especially for women.

Supported By: National Heart, Lung, and Blood Institute

2126‑PLeptin Is Associated with Sleep Quality in Patients with Obesity and Type 2 DiabetesTOMOE HIROTA, TOMOAKI MORIOKA, KOICHIRO YODA, NORIKAZU TOI, NORI-YUKI HAYASHI, SAORI MARUO, MASAFUMI KURAJOH, SHINSUKE YAMADA, TETSUO SHOJI, MASANORI EMOTO, MASAAKI INABA, Osaka, Japan

Abnormal sleep duration and quality have been increasingly recognized as risk factors of obesity, diabetes, and cardiovascular diseases. Recent evidence indicates that leptin, an adipocyte-derived hormone, associates short sleep duration with dysregulation of appetite and body weight in obesity. However, the clinical association between leptin and objectively measured sleep quality has not been fully investigated. Moreover, no study has examined the relationship between leptin and sleep duration/quality in patients with type 2 diabetes. In this study, we investigated the association between plasma leptin levels and sleep duration and quality in patients with type 2 diabetes. We included 185 patients with type 2 diabetes (mean age, 61 years; BMI, 26.6 kg/m2) of which 113 were obese (BMI ≥ 25kg/m2). We measured fasting plasma leptin levels by ELISA and objective sleep architec-ture by single-channel electroencephalography. We also measured apnea-hypopnea index (AHI), and nocturnal blood pressure (BP) by 24-h ambula-tory BP monitoring. In obese group (median BMI, 30.0 kg/m2), plasma leptin levels were positively associated with the delta power of the first sleep cycle, a marker of deep sleep (ρ = 0.248, p = 0.008). Multivariate analysis revealed that age (β = −0.657, p < 0.001) and BMI (β = −0.394, p = 0.003) were negatively, while plasma leptin levels were positively (β = 0.377, p = 0.010) associated with the delta power of the first sleep cycle, independent of sex, BMI, nocturnal systolic BP, eGFR, HbA1c, and AHI. On the other hand, plasma leptin levels were not significantly associated with the delta power of the first sleep cycle in nonobese group (median BMI, 22.5 kg/m2). Finally,

A559


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

2131‑PHigh Ratio of Abdominal Subcutaneous to Visceral Adipose Tis‑sue Is Associated with Preservation of Islet Beta‑Cell Function in Healthy individuals but Not in Those with Abdominal Glucometa‑bolic StatusJUAN LIU, HAI LI, WEIJIAN KE, LIEHUA LIU, YANBING LI, Guangzhou, China

Objecive: We aimed to investigate the relationship between abdominal adipose tissue distribution, β-cell function, and insulin sensitivity (IS) in a Chinese population with both normal and impaired glucometabolic status.

Subjects/Methods: A total of 552 individuals including 188 healthy sub-jects (healthy group), 239 with normal glucose and 1~4 abnormal metabolic traits (Metabolic Dysfunction group, MD group) and 125 with hyperglycemia (hyperglycemia group) were studied. HOMA-IR, HOMA B, Matsuda index, early-(I0-30/G0-30) and late-phase (I30-120/G30-120) insulin responses and the cor-responding disposition indexes (basal DI, early- and late-phase DIs) were calculated. Magnetic resonance spectroscopy was used to measure the area of abdominal subcutaneous adipose tissue (ASAT), visceral adipose tis-sue (VAT), and the ratio of ASAT to VAT (SVR) calculated.

Results: SVR was correlated positively with Matsuda index in healthy, MD and hyperglycemia groups (β=0.033, 0.035, 0.064, all P<0.05), and inversely with HOMA-IR (β=-0.036, -0.027, -0.06, all P<0.05). Multivariate-adjusted stepwise regression analysis showed that SVR was positively related with both early- and late-phase DI in the healthy group only (β=-0.023, -0.02, both P<0.05). In the healthy group, the hyperbolas of I0-30/G0-30 and I30-120/G30-120 vs. Matsuda index in the highest quarter of SVR were signifi-cantly right-shifted compared to those in the lowest (both P<0.05).

Conclusions: In healthy adults, higher SVR was a protective factor for β-cell function and IS, while in those with metabolic dysfunction or hyper-glycemia, higher SVR contributed to a relative better IS, which indicates abdominal SVR is possible to be an early and novel predicator of type 2 diabetes.

2132‑PExercise Fails to Prevent Fast‑Food‑Related Body Weight Increase In Healthy Adults: A 10‑Year Follow‑Up StudyJOHN DOUPIS, VASILEIOS ANDRIANESIS, CHRYSOULA KALLINIKOU, SPYRI-DOULA GLYCOFRIDI, VASILIKI PAPANDREOPOULOU, THEODOROS ANGELLOPOU-LOS, ALEXANDER KOKKINOS, Athens, Greece

Background and Aims: Obesity has been associated with the western type of diet, in combination with reduced exercise, in all age groups worldwide. In the present prospective study we examined the factors associated with the changes in body weight in a cohort of 284 young adults (mean age 31.1 ± 3.1 years; 8.8% females and 91.2% males) followed up for 10 years.

Materials and Methods: Body weight and height was measured in light clothing at baseline visit and BMI was calculated. A validated structured questionnaire was applied to collect data for food consumption, physical exercise, history of type 2 diabetes mellitus, and smoking habits. Follow-up data were obtained by self-reporting, 10 years later on a telephone inter-view.

Results: Over 10 years BMI was significantly increased in study popula-tion (p-value <0.001) [Wilcoxon Signed Ranks Test]. Multivariate logistic regression analysis showed (Hosmer and Lemeshow Test’s p-value=0.115) statistical association with the consumption of fast-food (p-value=0.023) and frequent (> 4 times per week) consumption of meat (p-value=0.021). Specifically, positive associations were found for the fast-food consumption (OR=10.34, 95% CI: 1.61-66.38, for the lowest vs. the highest consumption category) and for meat (OR=1.22, 95% CI: 0.34-4.35, for the lowest vs. the highest consumption category). Body weight changes were not associated with consumption of fruits, salads, refreshments, alcohol and physical exer-cise.

Conclusion: Our data suggest that fast food and frequent meat consump-tion (more than 4 times a week) are major determinants for body weight increase in a 10 year follow-up and that exercise failed to prevent this increase.

HbA1c, revealed that VFA is an independent contributor to GA/HbA1c (β=-0.378, p<0.001:R2=0.309).

In conclusion, VFA is a negative modulator for GA/HbA1c in type 2 diabetes.

2129‑PVisceral Adiposity (VA) Correlates Adversely with Cardiac Struc‑ture and Hemodynamics in Type 2 Diabetes (T2D)ANNE P. OFSTAD, ELSA ORVIK, SVEND AAKHUS, KÅRE I. BIRKELAND, LARS L. GULLESTAD, ODD E. JOHANSEN, Rud, Norway, Oslo, Norway

Obesity increases risk for heart failure (HF) in T2D, but the relationship between obesity and cardiac integrity is complex. We explored the associa-tion of anthropometrics and surrogate markers of VA and total body fat (TBF) to cardiac structure, function and hemodynamics. 133 T2D subjects without symptomatic HF (74% males, mean±SD age/T2D duration: 59±10/7±6 years, BMI 30.0±5.4 kg/m2) underwent clinical assessment including echocardiog-raphy (echo). VA was expressed by the index of central obesity (ICO), and waist-hip-ratio (WHR) whereas TBF was estimated (eTBF) by a validated for-mula. Cardiac structure indices were left ventricular (LV) mass and left atrial diameter (LAd), whereas function indices were measures of diastolic and systolic function. Cardiac hemodynamic indices were the rate pressure prod-uct (RPP), a marker of cardiac workload, and mean arterial pressure (MAP). Correlations were explored by Spearman’s Rho. Increasing WHR, BMI and ICO, but not eTBF, were associated with greater LAd and LV mass (Table). None of the adiposity markers correlated with cardiac function, however all, and in particular ICO (r=0.411), correlated with the RPP. ICO and eTBF also correlated with MAP. Adiposity markers of VA and TBF correlate adversely with cardiac structure and hemodynamics in T2D subjects. Further studies are needed to assess if adipose redistribution can restore this situation.

Supported By: South-Eastern Norway Regional Health Authority

2130‑P

WITHDRAWN

A560


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

2135‑PFish Oil Treatment Affects Adipose Tissue Inflammation and Insulin Sensitivity in Human ObesityJAMES D. HERNANDEZ, TING LI, JAMES MADURA, JUDY TIEDE, TONYA BEN-JAMIN, LORI ROUST, ELISABETH JACOBSEN, JAMES J. LEE, ELENA DE FILIPPIS, Scottsdale, AZ

Chronic low-grade inflammation of adipose tissue (AT) is a hallmark in obe-sity and insulin resistance (IR). Omental (OM) and subcutaneous (SC) AT from 6 obese, IR (BMI: 44+1.5 kg/m2) and 6 lean, insulin sensitive (IS) women (BMI: 22+1.5 kg/m2), undergoing abdominal surgery, with HOMA-IR: IR:5.0 + 1.6 vs. IS: 0.99 + 0.38, P<0.05 vs. IS, age matched were assessed for various inflam-matory markers. Q-RT PCR of pro-inflammatory genes demonstrated signifi-cantly increased levels in IR Sc and Om fat vs. IS subjects, (Sc TNFa:1.0 + 0.1 vs. 1.7 + 0.2; IL-6: 1.0 + 0.2 vs. 3.5 + 0.8 fold change (f.c); P<0.05)(Sc Om: TNFa: 1.0 + 0.1 vs. 1.7 + 0.2; IL-6: 1.0 + 0.2 vs. 2.2 + 0.4 f.c; P<0.05) and lower levels of Adiponectin (Sc:1.0 + 0.2 vs. 0.3 + 0.05 f.c.; P<0.05 vs. IS Sc; Om: 1.0 + 0.2 vs. 0.5 + 0.1; P<0.05 f.c. vs. IS Om), regardless of AT source. Plasma adi-ponectin (IS:10.9 + 3.1 vs. IR: 8.3 + 3.1 mg/l) and IL-6 (IS:0.7 + 0.22 vs. IR: 3.1 + 0.5 pg/ml P<0.05 vs. IS) followed AT patterns. Fish oil (FO) treatment was assessed for effect on inflammation and IS. After FO, IS improved and pro-inflammatory gene expression decreased, while Adiponectin, IL13 mRNA levels increased (Table). Our data suggest no disparity in AT inflammation between Om and Sc in obesity. FO also positively affects SC AT inflamma-tion and systemic IS. We venture that improved IS relates to changes in AT inflammation. Future studies will elucidate mechanism(s) responsible for such changes.

Table. Changes in Insulin Sensitivity and AT Inflammation in Six Obese, Insulin Resistant Subjects.Parameters Baseline (Bl) Post 3 mo FO (4gr/day) P valueGender (M/F) 5/1 5/1BMI (kg/m2) 43.5±1.8 43.6±2.0Rd (mg/kgFFM·min) 4.09±0.3 4.61±0.2 ≤0.05Il-6, RT-PCR (F.C. vs. Bl) 1±0 0.6±0.11 ≤0.05Mrc1, RT-PCR (F.C. vs. Bl) 1±0 0.66±0.16 ≤0.05Adipoq, RT-PCR (F.C. vs. Bl) 1±0 4.85±2.14 0.07Il-13, RT-PCR (F.C. vs. Bl) 1±0 3.81±1.28 ≤0.05

Supported By: Arizona Department of Health Services (14-00003606); Arizona Biomedical Research Commission; Kathryn H. and Roger Penske Career Develop-ment Award

2136‑PAssociation of Visceral Adipose Index and Body Fat Distribution Assessed by Using Dual‑Energy X‑Ray AbsorptiometryILSE Y MARTÍNEZ MUNOZ, ENEIDA DEL SOCORRO CAMARILLO ROMERO, TRINIDAD CORREA PADILLA, JONNATHAN SANTILLAN BENITEZ, MARÍA DEL SOCORRO CAMARILLO ROMERO, LAURA PATRICIA MONTENEGRO MORALES, JOSE DE JESUS GARDUNO GARCIA, Toluca, Mexico

Visceral adipose tissue (VAT) has been considered as the main respon-sible of the mechanisms for the development of insulin resistance and its metabolic consequences, even in normal weight people. Dual-energy X ray absorptiometry (DXA) system provides a quantitative assessment of visceral adiposity, however, clinical and research usefulness is not suitable due to cost and accessibility. Visceral Adipose Index (VAI) is a novel sex-specific index useful to evaluate visceral adipose function through a mathematical index that takes into account anthropocentric and metabolic parameters. The aim of the present study was to correlate VAI with different types of adipose tissue and lean mass measured by DXA. A prospective cross-sec-tional research was performed among 77 not smoking health women with normal and overweight with a mean age between 18.66± 0.66 years old and a body mass index of 24.35±3.03 kg/m², the mean of glucose, and lipid profile was into the normal parameters. As shown in Figure 1, VAI was correlated with mass VAT (r=0.328, p=0.004) and with fat distribution, being statisti-cally significance; total fat percentage (r=0.347, p=0.002), volume VAT tissue (r=0.328, p=0.004), whereas there was not significance with total lean mass (r=0.112, p=0.333).

In conclusion, VAI is a visceral adipose tissue subrogated indicator that could be useful for clinical practice.

2133‑PAir Pollution Has a Significant Impact on Intentional Efforts to Lose Weight: A Global Scale AnalysisSANG YOUL RHEE, MORENA USTULIN, IN JIN CHO, SO YOUNG PARK, SANG OUK CHIN, SUK CHON, JEONG TAEK WOO, YOUNG SEOL KIM, Seoul, Republic of Korea

Various environmental factors are known to have a significant impact on human health. However, most of the existing research results were con-fined to a specific region or population, making it difficult to generalize. In this study, we analyzed the effect of air pollution on human intentional weight loss on a global scale based on accumulated data in smartphone applications for weight loss. This study was based on weight record data of people who continued to use weight management application Noom. Among these, analysis was conducted with a focus on users in eight large cities (Chicago, Los Angeles, Detroit, New York, Seoul, Amsterdam, Berlin and London) around the world who have sufficient users and can obtain accurate air pollution data. The application data and the WHO ambient air pollution database were linked and analyzed. Annual value of PM 10 (ug/m3), and PM 2.5 were used. A total of 2,484 subjects were included in the study. The mean age was 38.2 years and the baseline BMI was 30.0 kg/m2. Accord-ing to the WHO criteria, 42% of the subjects were obese (BMI≥30 kg/m2). Among the cities included in the study, air pollution was highest in Seoul and Detroit was lowest. During the study period, the subject’s BMI decreased by an average of 2.1 kg/m2 (95% CI, 2.3 to 2.0). And approximately 80% of the subjects (n = 1,991) lost weight. In multivariate analysis, age, sex, dinner input frequency, physical activity input frequency, and mean daily calories intake were the main variables affecting weight loss (p<0.01). Particularly, PM10 (β=0.039, 95% CI 0.019 to 0.061, p=0.003) and PM2.5 (β=0.083, 95% CI 0.052 to 0.115, p<0.001) had significant effects on weight loss of subjects independently of other variables.

In conclusion, we have found that air pollution has a small but significant impact on intentional efforts to lose weight in humans. This result is the first of the relevant studies to be conducted on a global scale.

Supported By: Korean Ministry of Health and Welfare

2134‑PEffects of Obesity on Skeletal Muscle Biological Pathways Asso‑ciated with Subsarcolemmal vs. Intermyofibrillar Mitochondria Revealed by Proteomics AnalysisCHRISTOS S. KATSANOS, KATON A. KRAS, PAUL R. LANGLAIS, WAYNE T. WIL-LIS, ELENA A. DE FILIPPIS, LORI R. ROUST, Scottsdale, AZ, Tempe, AZ

Mitochondria form a reticulum across the muscle fiber, expanding from the subsarcolemmal region (subsarcolemmal mitochondria; SS Mito), to the intermyofibrillar region (intermyofibrillar mitochondria; IMF Mito). We inves-tigated whether obesity alters the ratio of SS-to-IMF individual Mito protein abundance and associated biological pathways. SS and IMF Mito fractions were isolated from vastus lateralis muscle samples using standard differen-tial centrifugation techniques, from sedentary lean (n=14; 7M/7F) and obese (n=15; 8M/7F) subjects (age: 34±3 vs. 33±3 years, P>0.05; BMI: 23±1 vs. 35±1 kg/m2, P<0.05; Matsuda insulin-sensitivity index: 11±1 vs. 4±1, P<0.05). Label-free quantitative proteomics was performed on the isolated Mito frac-tions, and abundance of individual proteins was quantified using Spectral Counting. Of the 306 Mito proteins consistently quantified between the SS and IMF Mito fractions, 24 proteins had SS-to-IMF Mito protein abundance ratio that differed (i.e., higher for 16 of the proteins) significantly between the lean and obese (P<0.05). The 24 proteins were further analyzed using the Reactome Database of biological pathways, and by accounting for the prob-ability that the overlap between the query and the pathway did not occur by chance and correcting for multiple comparisons. The following mitochon-drial biological pathways were upregulated in SS relative to IMF Mito in the obese subjects: Branched-chain amino acid catabolism, Respiratory electron transport/Complex I biogenesis, Protein translation initiation/elongation/termination. The overall findings describe remodeling of the mitochondrial reticulum in obese, insulin resistance subjects. They also provide evidence for redistribution of distinct biological processes regulating mitochondrial energy and protein metabolism from the intermyofibrillar to the subsarco-lemmal region mitochondria in obesity.


A561


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

while SAT (133.88±70.03g vs. 126.60±64.93g, p=0.487) showed no sta-tistical difference. VAT/SAT ratio was negatively correlated with L1-BMD (r=-0.493, p<0.001; r=-0.584, p<0.001), L2-BMD (r=-0.505, p<0.001; r=-0.570, p<0.001) and L3-BMD (r=-0.439, p<0.001; r=-0.579, p<0.001) in T2DM and nondiabetic women, respectively. The negative correlation remained signifi-cant after adjusting age, BMI, FBG, FIns and HbA1c (L1: r=-0.297, p=0.017; L2: r=-0.337, p<0.001; L3: r= -0.289, p=0.02) only in T2DM woman.

In conclusion, LS-BMD is negatively associated with VAT/SAT ratio in postmenopausal T2DM women, supporting the hypothesis that visceral adipose may be detrimental to bone quality in MS. Prospective studies are needed to confirm this.

2139‑PThe Change of Body Composition, Bone Metabolism Markers, and BMD in Chinese Severely Obese Patients after LSG: A Short‑Term StudyZHANG ZHIYIN, Shanghai, China

Laparoscopic sleeve gastrectomy (LSG) has been proved efficient in weight loss and improving abnormal metabolisms for severe obese patients, while the bone quality change after LSG is unclear. This study aimed to explore the longitudinal changes in bone metabolism markers and BMD with body composition alteration in obese patients after LSG during 6-month follow-up. A total of 41 males (31.3±9.5 years; BMI 40.1±5.1kg/m2) and 49 females (31.5±11.8 years, 39.6±5.0kg/m2) were recruited, and were fol-lowed 3 and 6 months after LSG. BMD was measured by dual-energy X-ray absorptiometry DXA) and quantitative computed tomography (QCT). Serum 25-hydroxyvitamin D (25-OHD), calcium, intact parathyroid hormone (iPTH), osteocalcin (OC), type I collagen cross-linked C-terminal telopeptide (CTX) were determined. There was no significant alteration for BMD during the whole study period in arm, rib, spine, pelvis, leg and total body evaluated by DXA, and also for lumber spine BMD by QCT (all p>0.05). Significant reduction of excess weight (EWL%), fat mass and lean mass was observed 6 months after LSG in male (-57.30± 16.99%, -30.6±12.7%, -16.7±6.8%; all p<0.001) and female (-61.78±16.82%, -36.5±9.2%, -21.7±8.1%, all p<0.001). Notably, CTX and OC increased significantly in males (141.1±66.2%, p<0.001; 78.0±46.2%, p=0.03) and females (188.6±144.5%, p<0.001; 83.0±68.5%, p<0.001) postoperatively. Calcium, 25-OHD and PTH showed no significant change during the study period.

In conclusion, no significant BMD change was observed in Chinese severe obese patients after LSG though significant weight loss and high bone turn-over. Long term follow-up is needed to confirm this.

2140‑PShort‑Term Intervention with Liraglutide and Metformin Increased Fertility Potential in a Subset of Obese PCOS Proceeding In Vitro SterilisationANDREJ JANEZ, VESNA SALAMUN, MOJCA JENSTERLE, EDA VRTACNIK BOKAL, Ljubljana, Slovenia

Objective: PCOS is the most common cause of anovulatory infertility, in particular when it is linked to obesity. Obese PCOS has poor IVF outcomes associated with impaired oocyte and embryo morphology. The aim of this study was to evaluate the impact of short-term weight intervention with metformin alone or in combination with liraglutide on fertility potential.

Design/Participants/Main Outcome Measure: A 12-week prospective randomized open-label study was conducted with 40 infertile obese PCOS patients (30,77± 3,742 aged years, BMI 36,69±3,51kg/m2, mean ± SD) who had been previously poor responders to lifestyle intervention. They were assigned to metformin (MET) 1000 mg BID or combined MET 1000 mg BID and low dose liraglutide 1.2 mg QD s.c. (COMBI) or to the control group (CON).

Results: Patients in MET lost on average 6,70±6,70 kg (P<0.001) compared with 7,68± 3,74 kg loss in COMBI group (P<0.001), COMBI not being superior to MET (P=0,103). In high responders who lost more than 5% of initial body weight numbers of blastocysts/patient were greater in both treatment arms than in controls (3,67±4,82 in COMBI; 3,60±6,95 in MET; vs. 2,09±2,07 in CON). High responders in COMBI also had the highest number of oocytes/patient 14,67±9,59 and the highest percentage of mature oocyte 11,22±9,27 among all three groups, although the between treatment differences were not statistically significant yet. Furthermore, in COMBI 3 (27%) patients became spontaneously pregnant before IVF in medication free period.

Conclusion: A subset of obese PCOS women who lost more than 5% of body weight had increased fertility potential. COMBI resulted in the highest number of women who lost more than 5% of weight and was associated with the highest number of blastocysts/patient. The high rate of spontaneous pregnancies in COMBI implicates the potential role of GLP-1 in reproduction.

Supported By: Centro de Investigación en Ciencias Médicas; Universidad Autónoma del Estado de México

2137‑PLower Serum Testosterone Levels in Obese Men with Acanthosis Nigricans and Improvement by Laparoscopic Sleeve GastrectomyZHU CUILING, Shanghai, China

Introduction: Acanthosis Nigricans (AN) is common in obese patients which is related to insulin resistance (IR), chronic inflammation and endo-crine problem. Here we measured the serum total testosterone (TT) and Interleukin-6 (IL-6) and their changes after Laparoscopic Sleeve Gastrectomy (LSG) in obese men with AN.

Methods: 141 obese patients without AN (OB group), 138 obese patients with AN (AN group), and 31 healthy volunteers (CON group) were recruited. 33 patients in AN group and 7 patients in OB group underwent LSG. The physical examination, serum hormone levels and general biochemical data were measured at baseline and 6 months after LSG. Logistic regression analysis was used to investigate the association between TT levels and AN.

Results: TT levels were lower in AN group and OB group than CON group and lowest in AN group (all P < 0.01). Fasting insulin (FINS), homoeostasis model assessment of insulin resistance (HOMA-IR) and IL-6 were higher in AN group than OB group, and both higher than CON group (all P < 0.01). Serum TT levels were negatively associated with FINS and HOMA-IR in AN and OB groups (all P < 0.05). The negative correlation of TT and IL-6 only occurred in AN group (P = 0.001). 6 months after LSG, TT levels were significantly increased while BMI and HOMA-IR were decreased in AN and OB groups (all P < 0.05). Notably, IL-6 was reduced in AN group (P = 0.005) but not in OB group (P > 0.05). Further investigation showed the change of TT was negatively associated with that of IL-6, HOMA-IR in AN group (r = -0.745, P < 0.001, r = -0.515, P = 0.020, respectively) but not in OB group. Logis-tic regression analysis revealed a significant inverse association between baseline TT levels and AN in obese men with final ORs = 0.089 and 95% CI = 0.021-0.379.

Conclusion: Male obese patients with AN had lower TT levels which may contribute to the insulin resistance and inflammation. The TT levels were greatly increased after LSG which may due to weight loss as well as the improvement of IR and inflammations.

Supported By: Fundamental Research Funds for the Central Universities (1501219107)

2138‑PLumbar BMD Is Negatively Associated with VAT/SAT Ratio in Post‑menopausal T2DM Evaluated by QCTZHANG ZHIYIN, Shanghai, China

Abdominal visceral obesity is the most important determinant for meta-bolic syndrome (MS). Patients with MS have high prevalence of osteoporotic fracture. The hypothesis is that visceral adipose may be detrimental to bone quality in MS. To study the relationship between visceral adipose area with BMD in postmenopausal women with T2DM, 249 patients (91 with T2DM and 158 with nondiabetics as matching group) were recruited in this study. Spine volumetric BMD (L1-L3), abdominal visceral adipose tissue area (VAT) and subcutaneous adipose tissue area (SAT) were analyzed by quantita-tive computed tomography (QCT). Age, height, fasting blood glucose (FBG), fasting serum insulin (FIns), fasting C-peptide (FCP) and HbA1c were mea-sured. Results showed that L3 level VAT (162.66±64.14 vs. 128.27±57.86 g, p<0.001), L1-BMD (105.11±30.18 vs. 92.69±29.20 mg/cm3, p=0.007), L2-BMD (97.82±30.83 vs. 85.38±29.14 mg/cm3, p=0.007), L3-BMD (93.00±29.90 vs. 79.96±29.06 mg/cm3, p=0.004) were significantly higher in T2DM group,

A562


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

Cox regression survival analysis, adjusted for covariates including cardio-vascular risk factors and comorbidities (cancer, chronic kidney disease, lung diseases), was performed.

Results: Only above class II obese patients (BMI >35) had an increased risk of cardiovascular death (HR 1.3 CI 95% 1.12-1.67). Sepsis mortality was reduced in overweight patients (BMI 25-30) HR 0.73 95% CI 0.62-0.88), with a trend for reduction in all obesity classes. Cancer mortality was reduced also in overweight patients (HR 0.79 95% CI 0.64-0.96). No difference across the BMI spectrum was found for peripheral vascular disease death.

Conclusion: This study shows that cardiovascular death increases for class II and III obesity in type 2 diabetes, but that patients who are over-weight (BMI 25-30) have reduced mortality which is driven by a lower risk of both cancer and sepsis related death.

Figure.

2144‑PEndogenous and Dietary Contributions to Advanced Glycation End‑productsNAILA RABBANI, MINGZHAN XUE, MARTIN O. WEICKERT, PAUL J. THORNALLEY, Coventry, United Kingdom

Accumulation of advanced glycation endproducts (AGEs) is linked to the development of obesity, diabetes and related vascular complications. AGEs are formed endogenously by protein glycation and are also absorbed from food. Dietary AGEs have low bioavailability; the amount absorbed is uncer-tain. New analytical approaches are required to resolve this. AGE exposure in the steady-state is equal to the flux of AGE excreted in urine - mainly AGE free adducts (glycated amino acids) originating from proteolysis of endog-enous AGE-proteins and dietary AGEs absorbed from food. Pyrraline is an AGE formed only in food, absorbed after digestion and excreted unmodified in urine. Where an AGE has significant dietary contribution, urinary AGE cor-relates positively with urinary pyrraline. Extrapolation of linear regression of urinary AGE on pyrraline gives an intercept (where pyrraline = 0) equal to endogenous AGE formation. The aim herein is to explore this to estimate fluxes of endogenous and dietary AGE exposure. Data from the HATFF study in overweight and obese subjects, n = 29 (NCT02095873), were used. Urinary AGEs were assayed by stable isotope dilution analysis LC-MS/MS (2nd void urine after overnight fasting). Median urinary excretion of pyrraline was 8.2-12.1 nmol/mg creatinine. Total urinary excretion of AGE, MG-H1, correlated positively with pyrraline for all 4 study visits, r = 0.43-0.63, P = 0.02. Linear regression revealed mean endogenous formation of MG-H1 was 13.3 nmol/mg creatinine, accounting for 67% total MG-H1 exposure; dietary exposure the remaining 33%. Similar analysis for CML, CEL, glucosepane (GSP) and pentosidine gave endogenous fluxes of 10.9, 3.0, 3.2 and 0.016 nmol/mg creatinine, respectively; 81% CML was of endogenous origin (although may vary with food type), with little dietary contribution to CEL, GSP and pento-sidine. We provide a methodology to assess quantitatively AGE exposure of endogenous and dietary origins. In overweight/obese subjects, most AGE exposure was of endogenous origin.

Supported By: Unilever; Innovate UK

2141‑PLong‑Term Body Composition Changes in Patients following Roux‑en‑Y Gastric Bypass vs. Sleeve GastrectomyKAREN J. HERSHKOP, HILA LEVI, LIMOR MARKO, LIOR HECHT, ANDREI KEIDAR, RAM WEISS, Jerusalem, Israel, Haifa, Israel, Petah Tikva, Israel

Background: Bariatric surgery is gaining acceptance as an effective long term weight loss solution. It is well established that some patients regain some of their weight several years following the procedure yet the changes in fat mass in this context are not well described.

Methods: We followed obese adults who underwent Roux-en-Y Gastric Bypass (RYGB) or Sleeve Gastrectomy (SG) for 7 years and assessed body composition dynamics using bioimpedance.

Results: 12 patients (7M/5F) underwent RYGB and 13 (3M/10F) underwent SG. Baseline BMI was comparable between the groups (42.5±4.3 kg/m2 vs. 43.4±5.4 kg/m2, p=0.6 for RYGB and SG respectively). The 7 year BMI was also comparable between the groups (32.2±2.8 kg/m2 vs. 33.5±5.8 kg/m2, p=0.5 for RYGB and SG respectively). Importantly, fat mass reached a trough at 12 months post op for both groups and significantly increased at the 7 years follow-up. Similarly percent of fat mass increased from12 month to 7 year follow-up in both operative procedures (4.6±4% vs. 5.5±4.8% for RYGB and SG respectively, p= 0.6). The ratio of fat mass to fat free mass significantly decreased at 1 year yet increased again at 7 years (0.49±1.7 vs. 0.61±1.6 for 12 month and 7 year respectively) for the whole group yet remained significantly lower than baseline.

Conclusions: RYGB and SG induce similar changes in body composition. The ratio of fat mass to fat free mass tends to decrease and remain below baseline at 7 years follow-up despite significant weight/BMI regain.

2142‑PMultidisciplinary Intensive Lifestyle Intervention in Patients with Type 1 Diabetes and Obesity: A Case‑Control StudyADHAM MOTTALIB, SHAHEEN TOMAH, TAHA ELSEAIDY, MEGAN KASETTY, AHMAD AL-MARADNI, JESSICA MAR, OSAMA HAMDY, Boston, MA

It has been long perceived that patients with type 1 diabetes (T1D) are frequently lean. However, recent reports indicated that ≈50% of patients with T1D are either overweight or obese. It was not known if weight man-agement is effective, maintainable or has any impact on glycemic control in patients with T1D in real-world clinical practice. This study was designed to evaluate the effect of intensive lifestyle intervention after one year follow-ing participation in the Weight Achievement and Intensive Treatment (Why WAIT) program, a 12-week multidisciplinary intensive lifestyle intervention (ILI) model designed for real-world clinical practice. We evaluated 68 adult patients with T1D enrolled in the program at Joslin Clinic between Sep-tember 2005 to August 2015 (mean age 42±11 yrs, females 62%, diabetes duration 23±12 yrs, A1c 8.3±1.0%, body weight 230±40 lbs, BMI 36.2±4.9 kg/m2) and matched them with a control group from the same practice dur-ing same period (age 42±12 yrs, females 62%, diabetes duration 21±10 yrs, A1c 8.3+1.0%, body weight 225±42 lbs, BMI 36.1±4.7 kg/m2). There were no significant differences between groups at baseline. At 1 year, body weight was significantly lower from baseline in ILI group (-17±20 lbs or -7.2±8.4%, p <0.001) but significantly increased in the control group (4±8 lbs or 2.0±3.9%, p <0.01). A1c decreased significantly in ILI group (-0.3±1.0%, p <0.05) but did not change from baseline in the control group. Between groups difference in body weight was also significant (p <0.001). No significant changes in lipid profile, blood pressure, renal function or medications were seen in both groups. Our results indicate that patients with T1D and obesity who enroll in multidisciplinary intensive lifestyle intervention, lose and maintain >7% of their initial body weight at one year in real-world clinical practice. That magnitude of weight loss is associated with a significant improvement in glycemic control.

2143‑PImpact of the Body Mass Index on the Cause of Mortality in Type 2 Diabetes from the “Obesity Paradox” CohortPIERLUIGI COSTANZO, DAVID HEPBURN, THOZHUKAT SATHYAPALAN, JOHN CLELAND, ANDREW CLARK, ERIC KILPATRICK, STEPHEN ATKIN, Cottingham, United Kingdom, Hull, United Kingdom, London, United Kingdom, Doha, Qatar

Background: We have previously reported a cohort study showing a reduced mortality risk for overweight patients with type 2 diabetes (the obe-sity paradox), despite having more cardiovascular hospitalization events. In this follow-up study we report the causes of death of these type 2 diabetes patients according to their Body Mass Index (BMI).

Methods: This cohort of 10,568 patients were followed-up for a median of 10.6 years and the cause of death for each patient identified from that reported to the Office for National Statistics, UK.

A563


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

2147‑PThe Effect of Jejunal Diversion, a Novel Malabsorptive Procedure, on Weight Reduction and Metabolic Control in Obese Subjects with Type 2 Diabetes MellitusMILOS MRAZ, JANA KLOUCKOVA, PETRA KAVALKOVA, ANNA CINKAJZLOVA, HELENA KRATOCHVILOVA, ZDENKA LACINOVA, PETRA SRAMKOVA, KARIN DOLEZALOVA, MARTIN FRIED, MARTIN HALUZIK, Prague, Czech Republic

Jejunal diversion (JD) is a novel metabolic surgical procedure using side-to-side jejuno-jejunostomy to create a partial intestinal by-pass in a less invasive manner compared with other malabsorbtive operations, thus far used predominantly in experimental animals. The aim of our study was to assess the effects of JD on anthropometric, metabolic and hormonal param-eters of patients with obesity and type 2 diabetes mellitus (T2DM). Fifteen obese T2DM subjects (8 males, aged 52.7 ± 6.1 years) were examined before and 3 and 12 months after JD. Postprandial effects of JD were evaluated using a 5-hour oral glucose tolerance test (oGTT). JD rapidly and sustainably reduced body weight (BMI 34.1 ± 3.5 vs. 31.9 ± 3.5 vs. 31.0 ± 3.7 kg/m2 for 0 vs. 3 vs. 12 months, p<0.001) and improved glucose control (HbA1c 78.9 ± 9.5 vs. 62.3 ± 11.4 vs. 54.1 ± 12.3 mmol/mol, p<0.001) and lipid profile (LDL 2.68 ± 0.72 vs. 1.94 ± 0.75 vs. 2.03 ± 0.80 mmol/l, p=0.014; triglycerides 3.67 ± 3.96 vs. 1.81 ± 0.99 vs. 1.86 ± 1.31 mmol/l, p=0.012). JD further augmented the incretin effect by increasing postprandial levels of GLP-1 along with the reduction of insulin and glucagon, while GIP, PP, amylin and ghrelin were not affected. Interestingly, bile acid levels peaked already 3 months after JD with a subsequent return to baseline at 12 months, in spite of no change being observed in their intestinal regulator fibroblast growth factor 19 (FGF-19). JD was accompanied by a reduction in serum ferritin (133.2 ± 97.6 vs. 66.9 ± 47.4 μg/l for 0 vs. 12months, p=0.004), vitamin B12 (491.6 ± 216.6 vs. 264.3 ± 139.5 ng/l, p<0.001) and zinc (16.2 ± 1.6 vs. 14.0 ± 2.8 mmol/l, p=0.013) without influencing any other nutritional parameters.

In conclusion, in obese subjects with T2DM JD induces significant weight loss and improvement in metabolic control that persist for at least 12 months after operation. Changes in GLP-1 and bile acids might be at least partially responsible for these effects.


2148‑PMeal Replacement Rescue of Nonresponders to Lifestyle Interven‑tion in the Pathobiology and Reversibility of Prediabetes in a Bira‑cial Cohort (PROP‑ABC) StudyIBIYE OWEI, AMY BREWER, CASEY PROVO, NKIRU UMEKWE, SAMUEL DAGOGO-JACK, Memphis, TN

The Pathobiology and Reversibilty of Prediabetes in a Biracial Cohort (PROP-ABC) study administers intensive lifestyle intervention (ILI) to initially normoglycemic offspring of parents with type 2 diabetes (T2DM) who devel-oped incident prediabetes during 5 years of follow-up. Participants receive individualized dietary and physical activity counseling, with a goal of achiev-ing 10% weight loss. In this report, we assessed the impact of meal replace-ment (MR) in participants who never met weight goal or regained weight after initial minimal weight loss on ILI. The MR plan comprised replacing breakfast and lunch with 2 “shakes” and 2 nutritional bars (40% carbs, 30% protein, 30% fat; 1200-1300 kcal/d for women and 1500-1600 kcal/d for men.

The participants (N=34), comprising 21 African American (AA) and 13 European American (EA), mean age 53.5 + 9.89 y, BMI 37.4 + 5.67 kg/m2, met weekly with research staff to collect MRs and undergo assessment. The mean (+ SD) duration of MR was 15.8 + 11.0 weeks (interquartile range 17 weeks). The total weight loss during the MR period was 164kg. The weight change (kg) was -2.68+ 1.51 at 4 wk, -4.32+ 1.75 at 8 weeks and -5.34 + 2.43 at 12 wk (P=0.0005) after MR. The magnitude of weight change post-MR was similar in AAs and EAs. In a multiple regression model with terms for duration of MR, age, sex, and race, the duration of MR (P=0.0014) was the only significant predictor of weight loss following meal replacement. Waist circumference decreased by 2.5 cm at 3 month post-MR and mirrored the pattern seen for weight.

In conclusion, meal replacement is an effective strategy for rapid induc-tion of weight loss in obese African American and European American subjects refractory to intensive lifestyle intervention. ClinicalTrials.gov ID: NCT02027571.


2145‑PDipeptidyl Peptidase‑4 (DPP‑4) Inhibitor Sitagliptin Improved Beta‑Cell Function and Prevented a Conversion Rate to MTG and DM2 in Metformin Intolerant PCOS with High Metabolic RiskSIMONA FERJAN, MOJCA JENSTERLE, ANDREJ JANEŽ, Ljubljana, Slovenia

Objective: Metformin is the first-line therapy for PCOS with high metabolic risk, yet a large proportion of patients cannot tolerate it due to associated gastrointestinal adverse events. The alternative pharmacological strategy when metformin cannot be tolerated is not well established in this popula-tion. Our aim was to evaluate whether sitagliptin (SITA) preserves metabolic profile in metformin (MET) intolerant PCOS with high metabolic risk.

Design and Methods: A 12-week prospective randomized open-label study was conducted with 30 obese MET intolerant women with PCOS (aged 35.0±7,2 years, BMI 36,9±5.5 kg/m2). They were randomized to lifestyle intervention and SITA 100mg QD or lifestyle intervention alone as controls (CON). All participants underwent standard anthropometric, endocrine mea-surements and OGTT. Model derived indexes of insulin resistance (IR) and β-cell function were calculated.

Results: SITA improved beta cell function as assessed by HOMA beta for 45,9±35,8 (p=0,001), modified beta cell function index (MBCI=I0XG0/(G120+G60-7)) for 7,9±7 (p=0,002) and QUICKI for -0,03±0,03 (p=0,002) and increased IR as assessed by HOMA-IR and insulin action index (IAI=1/G0XI0) for 1,8±1,7 (p=0,002) and -0,01±0,01(p=0,003). By contrast, beta cell function decreased in CON arm. The between group differences were significant for HOMA-beta (p=0,000), MBCI (p=0,010) and QUICKI (p=0,025). The conver-sion rate from normal glucose tolerance to impaired glucose tolerance (IGT) or T2DM was prevented in SITA (3/15 of subjects with MTG before and after the study). In CON 4 women had IGT at the beginning. After 12 weeks IGT was observed in 2 and T2DM in 3 subjects.

Conclusion: SITA improved beta cell function and prevented a conversion rate to IGT and T2DM in metformin intolerant PCOS with high metabolic risk when compared to lifestyle alone.

2146‑PPhysical and Cognitive Functions in Elderly Obese With and With‑out DiabetesALESSANDRA CELLI, BRYAN JIANG, STEPHEN DECKER, YOANN BARNOUIN, GEORGIA COLLELUORI, REINA ARMAMENTO-VILLAREAL, DENNIS VILLAREAL, Houston, TX

Background: Type 2 diabetes (T2D) and obesity are highly prevalent in older adults, due to sedentary lifestyles and increasing adiposity. Obesity exacerbates the physical and metabolic impairments that occur with aging, worsening quality-of-life. However, data on the role of diabetes on physical and cognitive functions in this specific population (elderly obese) are limited.

Objective: The purpose of this study was to evaluate physical and cogni-tive functions in elderly obese patients with T2D compared to elderly obese patients without T2D.

Methods: This is a cross-sectional study of baseline measurements in 307 older (65-85 yrs.) obese (BMI≥30 kg/m2) adults with T2D (Diabetes Group, DG) or without T2D (Control Group, CG). The outcomes were physical functions (Physical Performance Test [PPT] and peak oxygen consumption [VO2peak assessed during graded treadmill]) and cognitive functions (Modi-fied Mini-Mental State Exam [3MS], Word Fluency Test [WF], and Trail Mak-ing Test [Trails A and B].

Results: The DG (n=156) did not differ significantly from the CG (n=151) in age (70.1±3.8 vs. 69.7±4.6 yrs.; p=0.42) or BMI (36.1±5.3 vs. 36.3±4.6 kg/m2; p=0.74) but had higher diastolic BP (80.8±9.6 vs. 75.3±11.2 mmHg, p<0.001) and by study design, higher fasting blood glucose (126.7±42.7 vs. 98.0±17.1 mg/dL). The DG had lower VO2peak (16.7±3.5 vs. 17.9±3.6 ml/kg/min, p=0.003) but similar PPT scores than CG (27.9±4.6 vs. 28.4±2.5, p=0.20). With respect to cognitive functions, all scores were significantly lower in the DG (3MS: 92.7±11.9 vs. 95.9±4.9; WF: 17.9±5 vs. 19.4±5.5; Trail A 54.8±24.6 vs. 43.5±20.9 sec; Trail B 119.0±61.0 vs. 98.6±37.3 sec, all p value <0.05).

Conclusion: Diabetes interacts with obesity to further exacerbate physi-cal and cognitive impairments in the obese elderly population. Larger stud-ies are needed to determine if lifestyle change-induced weight loss will not only improve glycemic control but also the physical and cognitive functions and quality-of-life in the elderly obese with diabetes.

Supported By: American Diabetes Association (1-14-LLY-38 to D.V.)

A564


CATEGORY


Inte

grat

ed P

hysi

olog

y/O

besi

ty

POST

ERS


OBESITY—HUMAN

free fatty acids (FFA), insulin and GLP-1 were measured every 30 minutes for 3 hours after a test meal and area under the curve (AUC) for each was calculated. Body weight decreased 9.3 kg in both groups. Glucose AUC did not change significantly with weight loss in either group. (Diet: 16,350±311 to 16,096±275 mg/dl/min, p=0.42; GBS: 17,680±1,050 to 16,712±1,592 mg/dl/min, p=0.20). Fasting insulin (Diet: 28.5±7.3 to 7.6±1.8 ng/ml, p=0.03; GBS: 27.0±4.0 to 14.7±0.9 ng/ml, p=0.04) and insulin AUC (Diet: 11,197±1,350 to 5,537±568 ng/ml/min, p<0.001; GBS: 12,752±1,202 to 3,945±830 ng/ml/min, p<0.001) decreased in both groups, but no group differences were seen. HOMA-IR also improved with weight loss (Diet: 6.5±1.7 to 3.4±0.4, p=0.03; GBS: 6.4±0.7 to 3.3±0.4, p=0.02) but without a group effect. Fasting FFA (Diet: 645±52 to 851±66 μEq/L, p=0.01; GBS: 740±113 to 1,006±61 μEq/L, p=0.04) and FFA AUC (Diet: 85,136±5,505 to 107,840±6,443 μEq/L/min, p=0.007; GBS: 91,378±9,470 to 149,168±8,672 μEq/L/min, p<0.001) increased in both groups, with a greater increase in FFA AUC in the GBS group (p=0.03). GLP-1 AUC did not change in either group (Diet: 3,342±1,221 to 3,229±1,556 pmol/L/min, p=0.78; GBS: 1,488±272 to 2410±1,075 pmol/L/min, p=0.31).

In summary, short-term weight loss improved insulin sensitivity to a simi-lar degree with diet as compared to GBS. Caloric restriction and weight loss may be the most important determinants of early improvements in insulin sensitivity after GBS.


2151‑PGastric Plication and Duodenal‑Jejunal Bypass Liner Implantation Reduce Systemic and Adipose Tissue Inflammation without Affect‑ing Circulating Lipopolysaccharide Levels In Obese Subjects with Type 2 Diabetes MellitusANNA CINKAJZLOVA, ZDENKA LACINOVA, JANA KLOUCKOVA, PETRA KAVAL-KOVA, HELENA KRATOCHVILOVA, PAVEL TRACHTA, JARMILA KRIZOVA, KARIN DOLEZALOVA, MARTIN FRIED, MAREK BENES, ZUZANA VLASAKOVA, TEREZIE PELIKANOVA, MILOS MRAZ, MARTIN HALUZIK, Prague, Czech Republic

Low-grade inflammation is considered one of the key mechanisms linking obesity to type 2 diabetes mellitus (T2DM) with translocation of gut microbiota being suggested as its potential initiator. The aim of our study was to assess the effect of selected interventions on parameters of systemic and adipose tis-sue inflammation and intestinal leakage in obese subjects with T2DM. Thirty obese T2DM subjects (15 undergoing gastric plication (GP) and 15 endoscopic duodenal-jejunal by-pass liner implantation (DJBL)) and 10 healthy lean con-trols (C) were examined at baseline, 1 month and 6 (GP) and 10 months (DJBL) after intervention. Subcutaneous adipose tissue macrophages (ATM) were quantified using flow cytometry. Lipopolysaccharide binding protein (LBP) was used as a marker of circulating lipopolysaccharide levels and fatty acid binding protein 2 (FABP-2) as an indicator of intestinal leakage. At baseline, both GP and DJBL groups had increased hsCRP (3.3±1.1 and 3.5±0.8 vs. 0.7±0.3 mg/l for GP and DJBL vs. C, p=0.002) and LBP (15.4±1.1 and 14.0±1.5 vs. 9.8±0.7 μg/ml, p=0.002), while FABP-2 did not differ between groups. Postprocedurally, except of reduced body weight (BMI 42.4±1.3 vs. 36.0±1.3, p<0.001 for GP and 42.5±1.0 vs. 38.7±1.2, p<0.001 for DJBL), HbA1C (42.4±1.3 vs. 36.0±1.3 mmol/mol, p <0.001 for GP and 42.5±1.0 vs. 38.7±1.2 mmol/mol, p<0.001 for DJBL) and hsCRP (3.3±1.1 vs. 1.3±0.3 mg/l, p=0.040 for GP and 3.5±0.8 vs. 2.0±0.3 mg/l, p=0.069 for DJBL) both groups showed decreased amount of ATM (26.8±2.7 vs. 15.4±2.0%, p=0.008 for GP and 21.0±2.1 vs. 13.3±1.9%, p=0.027 for DJBL), while no effect was seen on LBP and FABP-2 levels.

To conclude, both interventions were associated with the reduction of systemic as well as subcutaneous adipose tissue inflammation. Modification of circulating lipopolysaccharide levels or gut leakage does not seem to play a role in these effects.


2152‑PObesity Progression and Incident Diabetes in the United States: A Retrospective Cohort StudyANDREW STOKES, BETHANY GRANT, CARINE HSIAO, STEPHEN JOHNSTON, ROBIN SCAMUFFA, Boston, MA, New Brunswick, NJ

Understanding patterns of obesity progression as well as the association between obesity progression and incident diabetes in the U.S. population is critical to intervention design. In this study, we used data from the National Health and Nutrition Examination Survey to assess obesity progression and the associated risks of developing diabetes across the life course. Weight progression was assessed using data on recalled weight at age 25 and 10 years prior to survey and incident diabetes status was ascertained using a retrospective cohort design, with follow-up spanning the 10-year inter-

2149‑PEffect of Lorcaserin in Different Age Groups: A Post‑hoc Analysis of Patients from the BLOOM, BLOSSOM, and BLOOM‑DM StudiesKEN FUJIOKA, ELENA NIKONOVA, SHARON ZHOU, CAROLINE APOVIAN, La Jolla, CA, Woodcliff Lake, NJ, Boston, MA

This post-hoc analysis evaluated the effect of lorcaserin, a serotonin (5-HT) 2C receptor agonist indicated for weight management, across age quartiles in order to assess if lorcaserin efficacy is altered in older patients. Dataset included lorcaserin Phase 3 studies in patients with overweight/obesity without type 2 diabetes (T2DM; BLOOM/BLOSSOM; body mass index [BMI] 27.0-29.9 kg/m2 and ≥1 comorbidity or BMI 30.0-45.0 kg/m2) and patients with overweight/obesity with T2DM (BLOOM-DM; BMI 27.0-45.0 kg/m2). Data are presented for patients randomized to receive LOR 10 mg twice daily or placebo plus diet and exercise for 52 weeks. Data-driven age quartile distribution differed between the BLOOM/BLOSSOM and BLOOM-DM studies. In BLOOM/BLOSSOM patients without T2DM, the odds of achieving ≥5% reduction in body weight (BW) at week 52 are significantly higher for patients >36 years (Table 1); BLOOM-DM patients with T2DM yielded no clear trend across age quartiles. Similar results were observed in lorcaserin-treated patients achieving ≥10% BW reduction and absolute weight loss. This study demonstrates that patients in older-age quartiles (>36 years) without T2DM had an increased response to lorcaserin therapy; in patients with T2DM, ubiquitous response was seen across age quartiles.

Table 1. Patients Achieving ≥5% Reduction in Body Weight at 52 Weeks of Treatment by Age Quartile.Age (Years)/Treatment N Responders

n (%)Odds Ratio(95% CI)*

POOLED BLOOM/BLOSSOMa

≤36 Placebo Lorcaserin

803856

144 (17.93)257 (30.02)

—2.01 (1.59, 2.54)

>36 to ≤45Placebo Lorcaserin

784770

148 (18.88)356 (46.23)

—3.70 (2.95, 4.66)


704735

164 (23.30)389 (52.93)

—3.70 (2.95, 4.64)

>53Placebo Lorcaserin

747737

231 (30.92)458 (62.14)

—3.68 (2.97, 4.57)

Age (Years)/Treatment N Responders n (%)

Odds Ratio(95% CI)**

BLOOM‑DMb

≤47Placebo Lorcaserin

7462

6 (8.11)16 (25.81)

—4.39 (1.55, 12.39)


6857

9 (13.24)17 (29.82)

—3.06 (1.19, 7.92)


4879

11 (22.92)36 (45.57)

—2.81 (1.25, 6.33)

>60Placebo Lorcaserin

5853

14 (24.14)25 (47.17)

—2.75 (1.21, 6.22)

Modified intent-to-treat population with last observation carried forward. CI=confidence interval. *From the logistic regression model, adjusting for baseline body weight and study. **From the logistic regression model, adjusting for baseline body weight, baseline HbA1c stratum, and baseline medication stratum. a P value for treatment by age quartile interaction <0.001. b P value for treatment by age quartile interaction = 0.920.

2150‑PSurgical vs. Diet‑Induced Weight Loss on Insulin SensitivityTANYA HALLIDAY, JASON TREGELLAS, JONATHAN SCHOEN, SARIT POLSKY, MARC CORNIER, Aurora, CO, Denver, CO

Gastric bypass surgery (GBS) is associated with significant improvements in glucose homeostasis and insulin sensitivity. It is not clear if these improve-ments are due to weight loss or other mechanisms. This study examined the effects of a comparable weight loss induced by GBS or liquid diet (Diet) on measures of metabolites and insulin metabolism. 17 Diet and 7 GBS individu-als without diabetes were studied at baseline and after 10 kg of weight loss. Each study period included a 3-day run-in diet and 1 day of testing. Glucose,

A565


CATEGORY


Isle

t Bio

logy

/In

sulin

Sec

retio

n

POST

ERS


ISLET BIOLOGY—APOPTOSIS

duces proinflammatory lipids that exacerbate β cell dysfunction and death. Inhibition of 12/15-LOX thereby provides a potential therapeutic approach to prevent glycemic deterioration in T1D, but to date no specific inhibitors have been tested T1D. Here we assessed the efficacy and mechanism of a novel and specific 12/15-LOX inhibitor, ML351. Using cultured β cells in vitro, ML351 exhibited no apparent toxicity across a range of concentration and led to improved survival in response to pro-inflammatory cytokines (PIC), which mimic the stress observed in T1D. In isolated mouse islets in vitro, ML351 inhibited production of the pro-inflammatory lipid mediator 12-hydroxyeicosa-tetraenoic acid, and in luciferase assays it dose-dependently increased activ-ity of the anti-oxidant transcription factor Nrf2. Following oral or intraperito-neal administration of ML351 in mice penetrance of the drug was observed in multiple organs, including pancreas, fat, liver and brain. In the low-dose streptozotocin model of T1D in mice, ML351 administration prevented devel-opment of diabetes, with coincident enhancement of nuclear Nrf2 in islet cells, reduced β oxidative stress, and preservation of β cell mass. In the non-obese diabetic mouse model of T1D, administration of ML351 in the predia-betic phase prevented glycemic deterioration and reduced invasive insulitis.

In conclusion, our data provide the first evidence to date that small mol-ecules that target 12/15-LOX can prevent progression of β cell dysfunction and glycemic deterioration in models of T1D.

Supported By: National Institutes of Health (T32DK064466), (R01DK105588 to R.G.M., J.L.N.); Diabetes Research Center (P30DK097512)

& 2155‑PPhysiologic Concentration of IL1β Enhances the Deleterious Effects of Islet AmyloidMAHNAZ MELLATI, DANIEL T. MEIER, THINN THINN KHINE, MEGHAN F. HOGAN, ANDREW T. TEMPLIN, SAKENEH ZRAIKA, REBECCA L. HULL, STEVEN E. KAHN, Seattle, WA, Melbourne, Australia

Islet amyloid formation by fibrillogenic human islet amyloid polypeptide (hIAPP) is associated with β-cell loss in human type 2 diabetes (T2D). Previ-ous in vitro studies have shown an association between islet amyloid for-mation and increased IL1β and TNFα levels, and in vivo reduced amyloid formation when blocking IL1β. As in healthy humans circulating IL1β levels are 0.5-12 pg/ml, we determined in vitro whether physiologic IL1β alone exacerbates amyloid deposition and islet inflammation and thereby a vicious cycle resulting in greater β-cell loss.

Based on IL1β dose-response studies (0.04-4000 pg/ml), we determined that 4 pg/ml recombinant mouse IL1β exacerbated amyloid formation in hIAPP transgenic islets more than 6 fold compared to when IL1β was absent (amyloid area/islet area: 3.85±0.9 vs. 0.6±0.23%, p=0.02, n=5). When hIAPP transgenic and non-transgenic islets were cultured in the presence or absence of 4 pg/ml IL1β for 48 hours, only when islet amyloid was pres-ent was IL1β treatment associated with reduced insulin but not IAPP gene expression, along with increased expression of iNOS and IL6 (Table).

In summary, in the presence of islet amyloid, IL1β at a physiological con-centration exacerbates islet amyloid formation, decreases insulin gene expression and enhances expression of pro-inflammatory response genes. Thus, blocking IL1β signaling may prevent amyloid-induced damage and pro-gression of T2D.

Table. Expression of Genes (Relative to Cyclophilin) in Non-Transgenic (NT) and hIAPP Transgenic (TG) Islets in Presence or Absence of 4 pg/ml IL1β.

NT + vehicle NT + IL1β TG + vehicle TG + IL1β a b cIapp 1.00±0.13 0.95±0.19 0.72±0.17 0.58±0.02 NS NS NSINS2 1.00±0.04 0.85±0.15 1.11±0.17 0.60±0.04 NS NS 0.02Nos2 1.00±0.95 1.70±0.53 0.40±0.19 6.80±0.90 NS NS 0.007IL6 1.00±0.43 2.05±0.78 1.73±0.82 4.09±0.55 NS NS 0.035IL1β 1.00±0.17 0.61±0.19 0.92±0.17 0.30±0.07 NS NS NSTNF 1.00±0.35 1.51±0.22 1.09±0.09 1.75±0.29 NS NS NSa = NT + vehicle vs. NT + IL1β; b = NT + vehicle vs. TG + vehicle; c = TG + vehicle vs. TG + IL1β; NS=non-significant; n=4.

& 2156‑PPregnancy‑Induced Proliferation of Human β‑Cells Engrafted into Immunodeficient NOD‑scid IL2rγnull MiceAGATA JURCZYK, ROHIT SHARMA, CHAOXING YANG, LEONARD SHULTZ, DALE GREINER, LAURA C. ALONSO, RITA BORTELL, Worcester, MA, Bar Harbor, ME

We and others have previously demonstrated that human β-cells in islet-engrafted immunodeficient mice can be induced to proliferate in response to hyperglycemia. The goal of this study was to determine the ability of human

val prior to survey. Cox models were used to compare the 10-year risks of developing diabetes across weight progression trajectories based on com-binations of body mass index (BMI) category at age 25 and 10 years prior to survey. 43% of individuals who started out in the normal category (BMI of 18.5-24.9) progressed to a higher weight class, with 33% progressing to overweight (25.0-29.9), 8% progressing to obese I (30.0-34.9) and 2.5% pro-gressing to obese II (35.0 and above). Among those who started out in the overweight and obese categories at age 25, rates of progression to a higher weight category were 42% and 45%. Compared to individuals who main-tained a normal weight, those who progressed to a higher weight status were at a significantly increased risks of developing diabetes, with hazard ratios of 2.49, 4.73 and 5.55 for those progressing to overweight, obese I and obese II. Weight stability was associated with a lower risk of diabetes com-pared to weight gain, however, those who were weight stable in overweight, obese I and obese II had significantly higher risks of developing diabetes than those who were stable normal weight, with hazard ratios of 2.87, 5.67 and 9.62. Individuals who lost weight between young adulthood and midlife had lower risks of developing diabetes than those who maintained weight in the higher category; however, they remained at higher risk than those who were normal weight in both periods.

ISLET BIOLOGY—APOPTOSIS

Moderated Poster Discussion: Life and Death of the Islet (Posters: 2153-P to 2158-P), see page 17.

& 2153‑PGenetic Deficiency of TXNIP Prevents Diabetes Progression in the Mouse Model of Wolfram SyndromeKIKUKO SHIINOKI, KATSUYA TANABE, MASAYUKI HATANAKA, RISA HARANO, HIROSHI MASUTANI, YUKIO TANIZAWA, Ube, Japan, Kyoto, Japan

Wolfram syndrome (WS), caused by the WFS1 gene mutations, is char-acterized by insulin dependent diabetes mellitus. Genetically determined pancreatic β cell loss results from augmented ER and oxidative stresses. TXNIP is induced in response to cellular stresses and is known to be involved in multiple cellular processes. WFS1-deficient islets have a robust increase in both TXNIP transcription and its protein levels compared to WT islets. We have recently found that WFS1-deficient β cells revert to endocrine progeni-tor like cells expressing Neurogenin3, and that a subset of them takes α cell fate. Importantly, such β cell plasticity appears preceding hyperglycemia and becomes more apparent along with the progression of hyperglycemia or in the setting of insulin resistance. Previously, we demonstrated piogli-tazone administration prevented β cell loss and rescued diabetes in WFS1-deficient mice carrying Ay/a (WFS1-/-;Ay/a). Interestingly, an increased islets TXNIP expression was prevented in the WFS1-/-;Ay/a mice, suggesting exces-sive TXNIP action has implications for the progression of β cell loss in the WFS1-/-;Ay/a mice. To test this hypothesis, WFS1-deficient mice in the pres-ence or the absence of the Ay/a mutation were crossed with the mice lacking TXNIP. WFS1-/-;Ay/a mice lacking TXNIP did not develop hyperglycemia in spite of having more weight gain compared to the nondiabetic obese Ay/a mice. Further, TXNIP-deficiency completely prevented diabetes progression in the mice lacking WFS1 (WFS1-/-;a/a) even after 40 weeks. Most antidia-betic effects of TXNIP-deficiency appear to be due to β cell preservation without loss of β cell phenotype nor α cells transduction. TXNIP-deficiency maintains β cell identity by a restoration of MafA expression and suppres-sion of Neurogenin3 emergence. These findings illustrate that inhibition of TXNIP is a novel therapeutic strategy for diabetes in WS and that TXNIP is a determinant of β cell plasticity in the setting of WFS1-deficiency.

Supported By: Japan Society for the Promotion of Science; MSD Life Science Foundation; Front Runner of Future Diabetes Research; Japan Association for Diabetes Education and Care

& 2154‑PInhibition of 12/15‑Lipoxygenase in Mouse Models of Type 1 Dia‑betesMARIMAR HERNANDEZ-PEREZ, SARAH TERSEY, RYAN M. ANDERSON, CHANELLE BENJAMIN, JERRY L. NADLER, THEODORE R. HOLMAN, DAVID J. MALONEY, RAGHAVENDRA G. MIRMIRA, Indianapolis, IN, Norfolk, VA, Santa Cruz, CA, Rockville, MD

Inflammation and oxidative stress are among the major factors that con-tribute to deficiency of β cell mass and insulin secretion in type 1 diabetes (T1D). 12/15-lipoxygenase (12/15-LOX) is induced in β cells during T1D, pro-

integrated physiology/obesity -...

Documents